Sequences

392,541 sequences

Number of 3's between n-th 2 and (n+1)st 2 in A026600.A026611
Number of 3's between n-th 2 and (n+1)st 2 in A026600.
a(n) = number of 1's between n-th 3 and (n+1)st 3 in A026600.A026612
a(n) = number of 1's between n-th 3 and (n+1)st 3 in A026600.
Number of 2's between n-th 3 and (n+1)st 3 in A026600.A026613
Number of 2's between n-th 3 and (n+1)st 3 in A026600.
a(n) least k > a(n-1) such that a(k)=s(n), for n >= 2, where s = A026600.A026614
a(n) least k > a(n-1) such that a(k)=s(n), for n >= 2, where s = A026600.
Triangle read by rows: T(n,0) = T(n,n) = 1 for n >= 0, T(n,1) = T(n,n-1) = 2*n-1 for n >= 1, T(n,k) = T(n-1,k-1) + T(n-1,k) for 2 <= k <= n-2 and n >= 4.A026615
Triangle read by rows: T(n,0) = T(n,n) = 1 for n >= 0, T(n,1) = T(n,n-1) = 2*n-1 for n >= 1, T(n,k) = T(n-1,k-1) + T(n-1,k) for 2 <= k <= n-2 and n >= 4.
a(n) = A026615(2*n, n).A026616
a(n) = A026615(2*n, n).
a(n) = A026615(2*n, n-1).A026617
a(n) = A026615(2*n, n-1).
a(n) = A026618(2*n, n-2).A026618
a(n) = A026618(2*n, n-2).
a(n) = A026615(2*n-1, n-1).A026619
a(n) = A026615(2*n-1, n-1).
a(n) = A026615(2*n-1, n-2).A026620
a(n) = A026615(2*n-1, n-2).
a(n) = A026615(n, floor(n/2)).A026621
a(n) = A026615(n, floor(n/2)).
a(n) = Sum_{k=0..n} A026615(n, k).A026622
a(n) = Sum_{k=0..n} A026615(n, k).
a(n) = Sum_{k=0..floor(n/2)} A026615(n, k).A026623
a(n) = Sum_{k=0..floor(n/2)} A026615(n, k).
a(n) = Sum_{j=0..n} Sum_{k=0..j} A026615(j, k).A026624
a(n) = Sum_{j=0..n} Sum_{k=0..j} A026615(j, k).
a(n) = Sum_{k=0..floor(n/2)} A026615(n-k,k).A026625
a(n) = Sum_{k=0..floor(n/2)} A026615(n-k,k).
Triangular array T read by rows: T(n,0) = T(n,n) = 1 for n >= 0, T(n,1) = T(n,n-1) = floor(3*n/2) for n >= 1, T(n,k) = T(n-1,k-1) + T(n-1,k) for 2 <= k <= n-2, n >= 4.A026626
Triangular array T read by rows: T(n,0) = T(n,n) = 1 for n >= 0, T(n,1) = T(n,n-1) = floor(3*n/2) for n >= 1, T(n,k) = T(n-1,k-1) + T(n-1,k) for 2 <= k <= n-2, n >= 4.
a(n) = A026626(2*n, n).A026627
a(n) = A026626(2*n, n).
a(n) = A026626(2*n, n-1).A026628
a(n) = A026626(2*n, n-1).
a(n) = A026626(2*n, n-2).A026629
a(n) = A026626(2*n, n-2).
a(n) = A026626(2*n-1, n-1).A026630
a(n) = A026626(2*n-1, n-1).
a(n) = A026626(2*n-1, n-2).A026631
a(n) = A026626(2*n-1, n-2).
a(n) = A026626(n, floor(n/2)).A026632
a(n) = A026626(n, floor(n/2)).
a(n) = Sum_{k=0..n} A026626(n, k).A026633
a(n) = Sum_{k=0..n} A026626(n, k).
a(n) = Sum_{k=0..floor(n/2)} A026626(n, k).A026634
a(n) = Sum_{k=0..floor(n/2)} A026626(n, k).
a(n) = Sum_{i=0..n} Sum_{j=0..n} A026626(i,j).A026635
a(n) = Sum_{i=0..n} Sum_{j=0..n} A026626(i,j).
a(n) = Sum_{k=0..floor(n/2)} A026626(n-k, k).A026636
a(n) = Sum_{k=0..floor(n/2)} A026626(n-k, k).
Triangular array T read by rows: T(n,0) = T(n,n) = 1 for n >= 0, T(n,1) = T(n,n-1) = floor((3*n-1)/2) for n >= 1, otherwise T(n,k) = T(n-1,k-1) + T(n-1,k) for 2 <= k <= n-2, n >= 4.A026637
Triangular array T read by rows: T(n,0) = T(n,n) = 1 for n >= 0, T(n,1) = T(n,n-1) = floor((3*n-1)/2) for n >= 1, otherwise T(n,k) = T(n-1,k-1) + T(n-1,k) for 2 <= k <= n-2, n >= 4.
a(n) = A026637(2*n, n).A026638
a(n) = A026637(2*n, n).
a(n) = A026637(2*n, n-1).A026639
a(n) = A026637(2*n, n-1).
a(n) = A026637(2*n, n-2).A026640
a(n) = A026637(2*n, n-2).
Number of nodes of even outdegree (including leaves) in all ordered trees with n edges.A026641
Number of nodes of even outdegree (including leaves) in all ordered trees with n edges.
a(n) = A026637(2*n-1, n-2).A026642
a(n) = A026637(2*n-1, n-2).
a(n) = A026637(n, floor(n/2)).A026643
a(n) = A026637(n, floor(n/2)).
a(n) = a(n-1) + 2*a(n-2) + 2, for n>=3, where a(0)= 1, a(1)= 2, a(2)= 4.A026644
a(n) = a(n-1) + 2*a(n-2) + 2, for n>=3, where a(0)= 1, a(1)= 2, a(2)= 4.
a(n) = Sum_{k=0..floor(n/2)} A026637(n, k).A026645
a(n) = Sum_{k=0..floor(n/2)} A026637(n, k).
a(n) = Sum_{i=0..n} Sum_{j=0..n} A026637(i,j).A026646
a(n) = Sum_{i=0..n} Sum_{j=0..n} A026637(i,j).
a(n) = Sum_{k=0..floor(n/2)} A026637(n-k, k).A026647
a(n) = Sum_{k=0..floor(n/2)} A026637(n-k, k).
Triangular array T read by rows: T(n,0)=T(n,n)=1 for n >= 0; for n >= 2 and 1<=k<=n-1, T(n,k)=T(n-1,k-1)+T(n-2,k-1)+T(n-1,k) if n is even and k is odd, else T(n,k)=t(n-1,k-1)+T(n-1,k).A026648
Triangular array T read by rows: T(n,0)=T(n,n)=1 for n >= 0; for n >= 2 and 1<=k<=n-1, T(n,k)=T(n-1,k-1)+T(n-2,k-1)+T(n-1,k) if n is even and k is odd, else T(n,k)=t(n-1,k-1)+T(n-1,k).
a(n) = T(2n,n), T given by A026648.A026649
a(n) = T(2n,n), T given by A026648.
a(n) = T(2n,n-1), T given by A026648.A026650
a(n) = T(2n,n-1), T given by A026648.
a(n) = T(2n,n-2), T given by A026648.A026651
a(n) = T(2n,n-2), T given by A026648.
a(n) = T(2n-1,n-1), T given by A026648.A026652
a(n) = T(2n-1,n-1), T given by A026648.
a(n) = T(2n-1,n-2), T given by A026648.A026653
a(n) = T(2n-1,n-2), T given by A026648.
a(n) = T(n,[ n/2 ]), T given by A026648.A026654
a(n) = T(n,[ n/2 ]), T given by A026648.
T(n,0) + T(n,1) + ... + T(n,n), T given by A026648.A026655
T(n,0) + T(n,1) + ... + T(n,n), T given by A026648.
a(n) = T(n,0) + T(n,1) + ... + T(n,[ n/2 ]), T given by A026648.A026656
a(n) = T(n,0) + T(n,1) + ... + T(n,[ n/2 ]), T given by A026648.
a(n) = Sum_{i=0..n, j=0..n} A026648(i,j).A026657
a(n) = Sum_{i=0..n, j=0..n} A026648(i,j).
Sum{T(n-k,k)}, 0<=k<=[ n/2 ], T given by A026648.A026658
Sum{T(n-k,k)}, 0<=k<=[ n/2 ], T given by A026648.
Triangular array T read by rows: T(n,0)=T(n,n)=1 for n >= 0; for n >= 2 and 1<=k<=n-1, if n is odd, then T(n,k)=T(n-1,k-1)+T(n-2,k-1)+T(n-1,k) if k is odd and <=[ n/2 ] or if k is even and >[ n/2 ]; in all other cases, T(n,k)=T(n-1,k-1)+T(n-1,k).A026659
Triangular array T read by rows: T(n,0)=T(n,n)=1 for n >= 0; for n >= 2 and 1<=k<=n-1, if n is odd, then T(n,k)=T(n-1,k-1)+T(n-2,k-1)+T(n-1,k) if k is odd and <=[ n/2 ] or if k is even and >[ n/2 ]; in all other cases, T(n,k)=T(n-1,k-1)+T(n-1,k).
T(2n,n), T given by A026659.A026660
T(2n,n), T given by A026659.