A167559 The row sums of triangle A167557.

1, 5, 46, 598, 10056, 207960, 5111856, 145721520, 4728528000, 172134253440, 6948393580800, 308058678385920, 14882061698380800, 778136819786726400, 43783908789625804800, 2638014817853286144000, 169455373956672285081600

Offset

1,2

Comments

Triangle A167557 is the lower left triangle of the ED1 array A167546.

Links

G. C. Greubel, Table of n, a(n) for n = 1..150

Formula

a(n) = Sum_{m=1..n} (4^(m-1)*(m-1)!*(n+m-2)!/(2*m-2)!).

Mathematica

Table[Sum[4^(m - 1) *(m - 1)! * (n + m - 2)!/(2*m - 2)!, {m, 1, n}], {n, 1, 10}] (* G. C. Greubel, Jun 15 2016 *)

Crossrefs

A167546 is the ED1 array.

Equals row sums of triangle A167557.

Sequence in context: A058478 A367256 A159608 * A367154 A121631 A071214

Adjacent sequences: A167556 A167557 A167558 * A167560 A167561 A167562

Keyword

easy,nonn

Author

Johannes W. Meijer, Nov 10 2009

Status

approved