A245560 Row sums of triangle in A144480.

1, 2, 6, 14, 36, 82, 196, 436, 1000, 2186, 4884, 10540, 23128, 49428, 107048, 227048, 486864, 1026394, 2183860, 4581244, 9686776, 20237372, 42571896, 88632664, 185653936, 385380932, 804316296, 1665340856, 3464899440, 7158117736, 14853106384

Offset

0,2

Links

Table of n, a(n) for n=0..30.

Formula

From N. J. A. Sloane, Aug 07 2014: if n is even, a(n) = (n+2)*2^(n-1)-(n/2)*binomial(n,n/2) otherwise a(n) = (n+2)*2^(n-1)-((n+1)/4)*binomial(n+1,(n+1)/2). This follows easily from the definition.

Maple

f:=n->if (n mod 2) = 0 then (n+2)*2^(n-1)-(n/2)*binomial(n, n/2)
else (n+2)*2^(n-1)-((n+1)/4)*binomial(n+1, (n+1)/2); fi;
[seq(f(n), n=0..40)];

Crossrefs

Cf. A144480.

Sequence in context: A362780 A323027 A110152 * A175654 A017922 A077937

Adjacent sequences: A245557 A245558 A245559 * A245561 A245562 A245563

Keyword

nonn,easy

Author

Roger L. Bagula, Oct 11 2008

Extensions

Edited with more terms by N. J. A. Sloane, Aug 07 2014

Status

approved