19131

Appears in sequences

• Expansion of 1/((1 - 6*x)*(1 - 10*x)*(1 - 11*x)*(1 - 12*x)).at n=3A028219
• Numbers k such that k and k^2 use only the digits 1, 3, 5, 6 and 9.at n=22A137035
• Numbers n such that n^6 + 272 is prime.at n=24A161998
• Number of (n+1)X(n+1) 0..2 arrays with no 2X2 subblock having the maximum of its diagonal elements greater than the absolute difference of its antidiagonal elements.at n=2A251105
• Number of (n+1)X(3+1) 0..2 arrays with no 2X2 subblock having the maximum of its diagonal elements greater than the absolute difference of its antidiagonal elements.at n=2A251108
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with no 2X2 subblock having the maximum of its diagonal elements greater than the absolute difference of its antidiagonal elements.at n=12A251113
• Digits of composite n end in n', where n' is the arithmetic derivative of n.at n=0A263024
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 539", based on the 5-celled von Neumann neighborhood.at n=26A272803
• Expansion of Product_{k>=1} 1/((1 - x^k)*(1 - x^(4*k))).at n=32A318027
• Number of vertices formed by drawing the lines connecting any two of the 2*(n+2) perimeter points of a 3 X (n+1) rectangular grid of points (or equally, a 2 X n grid of squares).at n=16A331763
• a(n) is the smallest positive integer which can be represented as the sum of n distinct nonzero tetrahedral numbers in exactly n ways, or -1 if no such integer exists.at n=21A360217
• Lesser of 2 successive sphenic numbers (k, k+4) sandwiching 3 consecutive nonsquarefree numbers.at n=26A363830
• Expansion of e.g.f. (1/x) * Series_Reversion( x/(1 + x^2/2*exp(x)) ).at n=7A371020
• Square array read by antidiagonals: T(n,k) is the number of n-tuples of nonnegative integers, not all equal to 0, with a shortest vectorial addition chain of length k; n >= 1, k >= 0.at n=58A383333