A059229 A diagonal of triangle defined in A059226.

0, 2, 12, 70, 426, 2708, 17846, 121014, 839388, 5929162, 42509318, 308561388, 2263197114, 16748071210, 124893822012, 937612685502, 7080464093282, 53748285892004, 409909445733950, 3139241855256334, 24132284421690988

Offset

1,2

Links

G. C. Greubel, Table of n, a(n) for n = 1..250

Index entries for sequences related to boustrophedon transform

Mathematica

T[i_, j_]:= T[i, j] = Module[{r, s, t1}, If[i == 0 && j == 0, Return[1]]; If[j == 0, Return[0]]; t1 = T[i, j - 1]; For[r = 0, r <= i - j, r++,
For[s = 0, s <= j, s++, If[r + s != i, t1 = t1 + T[r + s, s]]]]; Return[t1]]; Table[T[n, n - 1], {n, 1, 25}] (* G. C. Greubel, Jan 03 2017 *)

Crossrefs

Sequence in context: A026306 A116398 A001542 * A001251 A143357 A357831

Adjacent sequences: A059226 A059227 A059228 * A059230 A059231 A059232

Keyword

nonn

Author

N. J. A. Sloane, Jan 19 2001

Status

approved