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A124534
Row 4 of rectangular table A124530.
7
1, 1, 5, 25, 113, 608, 3535, 21844, 141809, 959882, 6738850, 48877221, 365145267, 2803002587, 22066904802, 177881536038, 1466278969213, 12345543329079, 106069531868783, 929158597546721, 8292429187449462, 75348425058995464
OFFSET
0,3
COMMENTS
In table A124530, the g.f. of row n, R_n(y), simultaneously satisfies: R_n(y) = Sum_{k>=0} y^k*R_k(y)^(n*k) for n>=0.
FORMULA
G.f.: A(x) = Sum_{n>=0} x^n*R_n(x)^(4n), where R_n(x) is the g.f. of row n in table A124530.
PROG
(PARI) a(n)=local(R); R=vector(n+5, r, vector(n+5, c, if(r==1 || c<=2, 1, r^(c-2)))); for(i=0, n, for(r=0, n, R[r+1]=Vec(sum(c=0, n, x^c*Ser(R[c+1])^(r*c)+O(x^(n+1)))))); R[5][n+1]
CROSSREFS
Cf. A124530 (table); other rows: A124531, A124532, A124533, A124535, A124536.
Sequence in context: A183926 A092440 A196985 * A369769 A261383 A089947
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Nov 05 2006
STATUS
approved