A212265 Row square-sums of triangle A096815.

1, 2, 3, 7, 21, 51, 138, 358, 969, 2735, 7514, 21372, 60144, 171510, 485294, 1388586, 3949211, 11296953, 32294750, 92471813, 265484354, 762548923, 2194099432, 6318266076, 18214160616, 52525201261, 151638570041, 437959067720, 1265890334086, 3661612407681

Offset

0,2

Links

Table of n, a(n) for n=0..29.

Mathematica

T[n_, k_] := T[n, k] = If[n < k || k < 0, 0, If[k = 1 || k == n, 1, Sum[T[n-k, j]T[k, k-j], {j, 0, k}]]]
Table[Sum[T[n, k]^2, {k, 0, n}], {n, 0, 50}]

Prog

(Maxima) T(n, k):= if ( n<k or k<0 ) then 0 else
if ( k<=1 or k=n ) then 1 else sum(T(n-k, j)*T(k, k-j), j, 0, k);
makelist(sum(T(n, k)^2, k, 0, n), n, 0, 20);

Crossrefs

Cf. A096815, A096816, A212264, A212421, A212422.

Sequence in context: A032223 A002863 A047693 * A107108 A323230 A262305

Adjacent sequences: A212262 A212263 A212264 * A212266 A212267 A212268

Keyword

nonn

Author

Emanuele Munarini, May 12 2012

Status

approved