%I
%S 1,8,45,416,1685,31032,229026,13856896,132843888,6551143600,
%T 672567897859,346984064352,51233511973865,99704578224832,
%U 1521740934249300,87595020192056292864,81891555365769626429,12883000343953567644,318718123756704667891346,50107182570391966040000,500792393469899639083500
%N Improved version of A002686; secondary main diagonal of A324124.
%C 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.
%H Petros Hadjicostas, <a href="/A328885/a328885.txt">Maple program</a>.
%H Yudell L. Luke, <a href="https://doi.org/10.1090/S00255718195200509938">Mechanical quadrature near a singularity</a>, Math. Comp. 6 (1952), 215219.
%Y Cf. A002685, A002686, A324124, A328866, A328884.
%K nonn
%O 1,2
%A _Petros Hadjicostas_, Oct 29 2019
