A377359 E.g.f. satisfies A(x) = ( 1 - log(1 - x*A(x))/A(x) )^3.
1, 3, 9, 57, 642, 9402, 177198, 4051338, 108926520, 3371293704, 118000461528, 4609447152120, 198791258476176, 9381618706074768, 480921576177145392, 26610634173004959312, 1580792845661466884352, 100345182367660427554560, 6778517964127816222982016
Offset: 0
Keywords
Programs
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PARI
a(n) = 3*sum(k=0, (3*n+3)\4, (3*n-3*k+2)!/(3*n-4*k+3)!*abs(stirling(n, k, 1)));
Formula
E.g.f.: B(x)^3, where B(x) is the e.g.f. of A377350.
a(n) = 3 * Sum_{k=0..floor((3*n+3)/4)} (3*n-3*k+2)!/(3*n-4*k+3)! * |Stirling1(n,k)|.