15138816

Appears in sequences

• Number of 3 X 3 symmetric matrices over Z(n) having nonzero determinant.at n=15A115225
• a(n) = binomial(n+6, 6)*8^n.at n=5A140406
• Decimal representation of the diagonal from the origin to the corner of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 974", based on the 5-celled von Neumann neighborhood.at n=23A290851
• Expansion of ((1 + 4*x)/(1 - 4*x))^(1/2).at n=13A304940
• Expansion of theta_4(theta_4(x) - 1), where theta_4() is the Jacobi theta function.at n=32A307186
• (1/4) times the sum of the elements of all subsets of [n] whose sum is divisible by four.at n=21A309296
• Number of compositions of partitions of 2n with exactly n compositions.at n=16A327550
• a(n) is the smallest number m such that tau(m) = n*tau(m-1) = n*tau(m+1) or 0 if no such m exists, where tau(k) = A000005(k).at n=33A350936