A171841 Row sums of triangle A171840.

1, 3, 8, 22, 68, 241, 974, 4410, 21969, 118698, 688301, 4250788, 27795353, 191545796, 1385868437, 10493852359, 82932266786, 682421525516, 5834572402059, 51734224244654, 474927065933637, 4507051910145879, 44154041028202657, 445971555581889956, 4638671662416764007

Offset

1,2

Links

Andrew Howroyd, Table of n, a(n) for n = 1..500

Example

a(4) = 22 = (1 + 2 + 4 + 15) since (1, 2, 4, 15) = row 4 of triangle A171840.

Prog

(PARI) \\ Needs Mtx() from A171840.
{ my(A=Mtx(30)); vector(#A, n, sum(k=1, n, A[n+1-k, n])) } \\ Andrew Howroyd, Sep 25 2025

Crossrefs

Cf. A171840.

Sequence in context: A092090 A011958 A260661 * A233449 A148770 A369791

Adjacent sequences: A171838 A171839 A171840 * A171842 A171843 A171844

Keyword

nonn

Author

Gary W. Adamson, Dec 19 2009

Extensions

a(13) onwards from Andrew Howroyd, Sep 25 2025

Status

approved