A193848 Triangular array: (1/2)*A193846.

1, 2, 4, 4, 14, 13, 8, 40, 68, 40, 16, 104, 256, 284, 121, 32, 256, 824, 1336, 1094, 364, 64, 608, 2416, 5144, 6196, 4010, 1093, 128, 1408, 6656, 17536, 27824, 26608, 14216, 3280, 256, 3200, 17536, 55040, 108256, 136688, 108256, 49208, 9841, 512

Offset

0,2

Links

Andrew Howroyd, Table of n, a(n) for n = 0..1325 (rows 0..50)

Formula

G.f.: 1/(1 - 2*(1 + 2*y)*x + y*(2 + 3*y)*x^2). - Andrew Howroyd, Feb 18 2024

Example

Triangle begins:
    1;
    2,    4;
    4,   14,   13;
    8,   40,   68,    40;
   16,  104,  256,   284,   121;
   32,  256,  824,  1336,  1094,   364;
   64,  608, 2416,  5144,  6196,  4010,  1093;
  128, 1408, 6656, 17536, 27824, 26608, 14216, 3280;
  ...

Mathematica

(See A193846.)

Prog

(PARI) T(n)={[Vecrev(p) | p<-Vec(1/(1 - 2*(1 + 2*y)*x + y*(2 + 3*y)*x^2) + O(x*x^n))]}
{ my(A=T(10)); for(i=1, #A, print(A[i])) } \\ Andrew Howroyd, Feb 18 2024

Crossrefs

Cf. A193846.

Sequence in context: A341235 A363649 A263023 * A371254 A218974 A221706

Adjacent sequences: A193845 A193846 A193847 * A193849 A193850 A193851

Keyword

nonn,tabl

Author

Clark Kimberling, Aug 07 2011

Status

approved