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A147766 Successive differences of A000990. 3
1, 0, 2, 2, 5, 6, 13, 16, 30, 40, 66, 90, 142, 192, 290, 396, 575, 782, 1112, 1500, 2092, 2808, 3848, 5132, 6945, 9192, 12298, 16178, 21422, 28000, 36763, 47748, 62205, 80334, 103910, 133458, 171538, 219150, 280039, 356020, 452469, 572548, 724047 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Original definition: A000012^(-1) * A000990, where A000012^(-1) = the pairwise difference operator and A000990 = (1, 1, 3, 5, 10, 16, 29, 45, ...).

Triangle A147767 is constructed from A147766 in every column.

LINKS

Table of n, a(n) for n=0..42.

FORMULA

a(n) = A000990(n) - A000990(n-1) and a(0)=1.

G.f.: exp(2*Sum_{k>=1} (sigma_1(k) - 1)*x^k/k). - Ilya Gutkovskiy, Aug 21 2018

a(n) ~ exp(2*Pi*sqrt(n/3)) * Pi^2 / (4 * 3^(7/4) * n^(9/4)). - Vaclav Kotesovec, Aug 21 2018

EXAMPLE

A000990 = (1, 1, 3, 5, 10, 16, ...). Pairwise differences = (1, 0, 2, 2, 5, ...).

CROSSREFS

Cf. A000990, A147767.

Sequence in context: A181716 A098600 A261866 * A034420 A304867 A303931

Adjacent sequences:  A147763 A147764 A147765 * A147767 A147768 A147769

KEYWORD

nonn

AUTHOR

Gary W. Adamson, Nov 11 2008

EXTENSIONS

Definition changed and more terms added by Olivier Gérard, Jul 25 2016

STATUS

approved

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Last modified May 25 16:14 EDT 2022. Contains 354071 sequences. (Running on oeis4.)