20376

Appears in sequences

• Coordination sequence for {E_6}* lattice.at n=4A008401
• a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (1, p(1), p(2), ...), t = (F(2), F(3), F(4), ...).at n=15A025101
• Consider all integer triples (i,j,k), j,k>0, with i^3=j^3+binomial(k+2,3), ordered by increasing i; sequence gives j values.at n=32A054235
• Numbers n such that A118799(n) = 0.at n=8A118578
• Triangle T, read by rows, where column k of T equals (k+1)*(column k of T^2) when shifted to have an initial '1'; i.e., T(n,k) = (k+1)*[T^2](n-1,k) for n>k>=0, with T(n,n)=1 for n>=0.at n=50A123305
• G.f.: A(x) = (A_1)^2 where A_1 = 1/[1 - x*(A_2)^2], A_2 = 1/[1 - x^2*(A_3)^2], A_3 = 1/[1 - x^3*(A_4)^2], ... A_n = 1/[1 - x^n*(A_{n+1})^2] for n>=1.at n=13A132333
• a(n) = 2*n*A071148(n).at n=17A177082
• First number of divisor symmetry n: d(n-k) = d(n+k) for 1 <= k <= n, but d(n-k-1) != d(n+k+1).at n=4A202463
• Number of (n+2) X (2+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 01010101 or 01010111.at n=7A260132
• T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00010101 01010101 or 01010111.at n=37A260138
• T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00010101 01010101 or 01010111.at n=43A260138
• Number of nXnXn triangular 0..5 arrays with new values introduced in sequential zero-upwards order and exactly one 2x2x2 triangle having values all equal.at n=3A271073
• T(n,k)=Number of nXnXn triangular 0..k arrays with new values introduced in sequential zero-upwards order and exactly one 2x2x2 triangle having values all equal.at n=31A271075
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 454", based on the 5-celled von Neumann neighborhood.at n=42A272278
• a(n) is the sum of quadratic nonresidues of A002145(n) (the n-th prime == 3 mod 4).at n=31A282036
• Let p = n-th prime == 3 mod 8; a(n) = sum of quadratic nonresidues mod p .at n=15A282726
• The number of grains of sand in the identity element for the 3D sandpile group on an n X n X n cubic grid.at n=16A351379
• a(n) = Sum_{i+j+k=n, i,j,k >= 1} sigma(i) * sigma(j) * sigma(k).at n=14A374951