19328

Appears in sequences

• 6-dimensional centered tetrahedral numbers.at n=10A008500
• Coordination sequence for alpha-Mn, Position Mn3.at n=36A009952
• Coordination sequence for alpha-Mn, Position Mn4.at n=36A009953
• Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 69.at n=35A031567
• Number of trees with n nodes and 4 leaves.at n=41A055291
• a(0) = 1; for n>0, a(n) = number of distinct sums of subsets of {1, 1/2, 1/3, 1/4, ..., 1/n} (allowing the empty subset).at n=16A072207
• a(n) = -a(n-1) -a(n-2) -a(n-3) +a(n-4), a(0)=0, a(1)=1, a(2)=-1, a(3)=0.at n=43A100329
• Triangle T(n, k) = 2^(k-1) * E(n, k-1) where E(n,k) are the Eulerian numbers A173018, read by rows.at n=24A142075
• Number of permutations of 1..n arranged in a circle with exactly 4 adjacent element pairs in decreasing order.at n=4A151577
• a(n+1)-+a(n)=prime, a(n+1)*a(n)=Average of twin prime pairs, a(1)=3,a(2)=10.at n=29A154496
• T(n, k) = E(n, k)*2^k where E(n,k) are the Eulerian numbers A173018, for n > 0 and 0 <= k <= n-1, additionally T(0,0) = 1.at n=25A156365
• First differences of A160644.at n=34A160646
• Maxima in A163169.at n=42A163172
• Number of binary strings of length n with equal numbers of 00000 and 00110 substrings.at n=15A164183
• A symmetrical triangle: T(n,k) = A008292(n+1, k) * f(n,k), where f(n,k) = 2^k when floor(n/2) >= k, otherwise 2^(n-k).at n=24A174303
• Products of the 7th power of a prime and a distinct prime (p^7*q).at n=37A179664
• E.g.f. satisfies: A(x) = ( exp(x*A(x)) + exp(x*A(-x)) )/2.at n=7A198198
• Number of (n+1) X 7 0..1 arrays with the number of clockwise edge increases in every 2 X 2 subblock differing from each horizontal or vertical neighbor.at n=12A205191
• Number of (n+2)X5 0..1 matrices with each 3X3 subblock having the same population.at n=3A224646
• Number of (n+2)X6 0..1 matrices with each 3X3 subblock having the same population.at n=2A224647