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A128572
Row 2 of table A128570.
10
1, 3, 24, 288, 4440, 82080, 1752000, 42178800, 1127335680, 33073099200, 1055891810880, 36435757294080, 1351364788224000, 53617083034314240, 2266453101278568960, 101705245560225146880, 4829501671573344393600
OFFSET
0,2
LINKS
FORMULA
G.f.: A(x) = 1 + 3x*R(x,3)^2, where R(x,3) = 1 + 4*x*R(x,4)^2, R(x,4) = 1 + 5*x*R(x,5)^2, ..., R(x,n) = 1 + (n+1)*x*R(x,n+1)^2, ... and R(x,n) is the g.f. of row n of table A128570.
a(n) ~ 8*n^2*A128318(n)/9. - Vaclav Kotesovec, Mar 19 2016
PROG
(PARI) {a(n)=local(A=1+(n+3)*x); for(j=0, n, A=1+(n+3-j)*x*A^2 +x*O(x^n)); polcoeff(A, n)}
CROSSREFS
Cf. A128570 (triangle), other rows: A128318, A128571, A128573, A128574, A128575, A128576; A128577 (square of row 0), A128578 (main diagonal), A128579 (antidiagonal sums).
Sequence in context: A355426 A064037 A257453 * A052592 A059381 A301933
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Mar 11 2007
STATUS
approved