A154381 Row sums of Bell related number triangle A154380.

1, 2, 6, 20, 72, 276, 1120, 4804, 21796, 104784, 534788, 2901580, 16742440, 102654356, 667519492, 4590552960, 33278208004, 253436345340, 2020974497112, 16823488830836, 145798111066964, 1312272490908464

Offset

0,2

Comments

a(n) = 2*A129247(n), n>0. Hankel transform is 2^n*A000178(n).

Links

Table of n, a(n) for n=0..21.

Formula

G.f.: 1/(1-2x/(1-x/(1-x/(1-2x/(1-x/(1-3x/(1-x/(1-4x/(1-... (continued fraction).

Crossrefs

Cf. A000110, A000178, A129247, A154380.

Sequence in context: A348351 A150134 A059279 * A150135 A150136 A195186

Adjacent sequences: A154378 A154379 A154380 * A154382 A154383 A154384

Keyword

easy,nonn

Author

Paul Barry, Jan 08 2009

Status

approved