19020

Appears in sequences

• Icosahedral numbers: a(n) = n*(5*n^2 - 5*n + 2)/2.at n=19A006564
• Pisot sequence E(8,10), a(n) = floor( a(n-1)^2/a(n-2) + 1/2 ).at n=31A010916
• Numbers k such that k^3 has only even digits.at n=18A052004
• a(n) = (n + 2)*(2*n^2 - n + 3)/6.at n=38A056520
• Number of n-element unlabeled ordered T_0-antichains without isolated vertices; number of T_1-hypergraphs (without empty edge and without multiple edges) on n labeled vertices.at n=4A059523
• a(n) = (2*n-1)*(5*n^2-5*n+6)/6.at n=22A063489
• a(n) = 49n^2 - 28n - 20.at n=19A118058
• Triangle read by rows: T(n,k) is the number of ternary words of length n on {0,1,2}, having k isolated 0's (n >= 0, k >= 0).at n=37A120924
• a(n) = 1000*n + 20.at n=18A157510
• a(n) = Hermite(n,6).at n=4A158516
• The 4th Hermite Polynomial evaluated at n: H_4(n) = 16n^4 - 48n^2 + 12.at n=6A163323
• Number of binary strings of length n with equal numbers of 00101 and 01001 substrings.at n=15A164244
• a(n) is the sum of all distinct integers that can be produced by reversing the digits of n in any base b >= 2.at n=57A211518
• Number of 2 X n 0..2 arrays with antidiagonals unimodal and rows and diagonals nondecreasing.at n=18A224000
• Number of (n+1) X (7+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=11A253434
• Number of (7+1) X (n+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=11A253441
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 417", based on the 5-celled von Neumann neighborhood.at n=31A272018
• Number of permutations of [n] whose cycle lengths are Fibonacci numbers.at n=8A273001
• Expansion of (6*x^5+5*x^4+4*x^3+3*x^2+2*x+8)/(1-x-x^6).at n=31A275627
• Total number of triangular numbers in all compositions of n.at n=13A309536