20172

Appears in sequences

• Tricapped prism numbers.at n=23A005920
• Number of perfect matchings in graph C_{14} X P_{n}.at n=3A028485
• Base-9 palindromes that start with 3.at n=26A043030
• a(n) = 4*((n-1)! + 1) + n.at n=7A073829
• 75-gonal numbers: a(n) = n*(73*n-71)/2.at n=24A098230
• Number of perfect matchings in the C_{2n} X P_3 graph (C_{2n} is the cycle graph on 2n vertices and P_3 is the path graph on 3 vertices).at n=6A102091
• a(n) = 12*n^2.at n=41A135453
• Omit the initial 1 from A000141 and take the Mobius transform.at n=40A190622
• Number of nonzero terms in A117943 up to index 2^n: a(n) = Sum_{k=1..2^n} A117943(k).at n=16A255822
• Sum of distinct terms of A002674: a(0) = 0, a(2n) = A255411(A153880(a(n))), a(2n+1) = 1+A255411(A153880(a(n))).at n=10A275959
• Numbers that are the sum of three squares in arithmetic progression.at n=33A292313
• Number of set partitions of [n] where all subsets are partitioned into the same number of nonempty subsets.at n=8A324238
• Number of edges formed in a square by straight line segments when connecting the n+1 points along each edge that divide it into n equal parts to the n+1 points on the edge on the opposite side of the square.at n=8A355840
• Numbers w + x + y + z where (w,x,y,z) are nonnegative solutions to the Diophantine equation w^2 + x^2 + y^2 + z^2 = w*x*y*z.at n=12A385713
• Perimeters of nondegenerate triangles with integer areas, whose side lengths are triangular numbers.at n=38A385737