23950080

Appears in sequences

• Expansion of e.g.f. (1-x)/(1-x-2*x^2+x^3).at n=9A052672
• Decomposition of Stirling's S(n,2) based on associated numeric partitions.at n=32A058936
• Sixth (unsigned) column sequence of triangle A062139 (generalized a=2 Laguerre).at n=5A062195
• Size of largest conjugacy class in A_n, the alternating group on n symbols.at n=11A070733
• Generalized Stirling2 array (4,2).at n=30A090438
• a(1) = 1, a(n) = a(n-1) if n = 1 (mod 3), otherwise n*a(n-1).at n=13A123144
• Denominators in expansion of 1/(Sum_{n >= 0} (x^n/n!)*binomial(2n,n)/(n+1)).at n=12A178957
• Number of (n+2) X (n+2) symmetric binary matrices without the pattern 0 1 1 diagonally.at n=4A190535
• a(n) = v(n+1)/v(n), where v=A203430.at n=8A203431
• Young urn sequence (number of possible evolutions in n steps of the "Young" Pólya urn).at n=9A293653
• a(n) = Product_{k=1..n} (Fibonacci(k+2) - 1).at n=8A302999
• Fourier coefficients of Eisenstein series of degree 2 and weight 4: a(n) = coefficient of the matrix [n, 0; 0, 1] with determinant n.at n=13A323991
• Number of permutations of [n] with distinct cycle lengths such that each cycle contains exactly one cycle length different from its own as an element.at n=12A364283
• Numbers of least prime signature (A025487) whose prime factorization has equal sum of even and odd exponents.at n=17A371600
• Numbers whose divisors have a mean abundancy index that is larger than 3.at n=7A374779