

A328885


Improved version of A002686; secondary main diagonal of A324124.


6



1, 8, 45, 416, 1685, 31032, 229026, 13856896, 132843888, 6551143600, 672567897859, 346984064352, 51233511973865, 99704578224832, 1521740934249300, 87595020192056292864, 81891555365769626429, 12883000343953567644, 318718123756704667891346, 50107182570391966040000, 500792393469899639083500
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OFFSET

1,2


COMMENTS

Sequence A002686 has only 10 terms (from n = 1 to n = 10). We have a(n) = A002686(n) for 1 <= n <= 10 except for n = 7: a(7) = 229026 while A002686(7) = 1603182 (which is a(7) * 7 = 229026 * 7). For an explanation, see the comments for array A324124. This is necessary to give a unique definition to the terms of array A324124.


LINKS

Table of n, a(n) for n=1..21.
Petros Hadjicostas, Maple program.
Yudell L. Luke, Mechanical quadrature near a singularity, Math. Comp. 6 (1952), 215219.


CROSSREFS

Cf. A002685, A002686, A324124, A328866, A328884.
Sequence in context: A006887 A009369 A120044 * A002686 A306047 A110348
Adjacent sequences: A328882 A328883 A328884 * A328886 A328887 A328888


KEYWORD

nonn


AUTHOR

Petros Hadjicostas, Oct 29 2019


STATUS

approved



