A180749 G.f.: A(x) = x/Series_Reversion(x*G(x)) where G(x) = Sum_{n>=0} (n+1)^n*x^n.

1, 2, 5, 26, 231, 2844, 43854, 803578, 16960731, 404010692, 10705681566, 312189558548, 9933838621998, 342530711507568, 12724338381577576, 506700249728722586, 21535304484380633171, 973107015782753948460

Offset

0,2

Links

Paul D. Hanna, Table of n, a(n) for n = 0..300

Formula

G.f. satisfies: [x^n] A(x)^(n+1) = (n+1)^(n+1) for n>=0.

G.f. satisfies: A(x) = G(x/A(x)) where A(x*G(x)) = G(x) = Sum_{n>=0} (n+1)^n*x^n.

Example

G.f.: A(x) = 1 + 2*x + 5*x^2 + 26*x^3 + 231*x^4 + 2844*x^5 +...
G.f. satisfies A(x) = G(x/A(x)) where A(x*G(x)) = G(x) begins:
G(x) = 1 + 2*x + 3^2*x^2 + 4^3*x^3 + 5^4*x^4 + 6^5*x^5 + 7^6*x^6 +...
so that:
A(x) = 1 + 2*x/A(x) + 3^2*x^2/A(x)^2 + 4^3*x^3/A(x)^3 + 5^4*x^4/A(x)^4 +...
The coefficients in A(x)^n for n=1..8 begin:
A^1: [(1), 2,   5,   26,  231,  2844,   43854,    803578, ...];
A^2: [1,  (4), 14,   72,  591,  6872,  102070,   1823024, ...];
A^3: [1,   6, (27), 146, 1140, 12546,  179105,   3112332, ...];
A^4: [1,   8,  44, (256),1954, 20488,  280848,   4740128, ...];
A^5: [1,  10,  65,  410,(3125),31512,  415020,   6793750, ...];
A^6: [1,  12,  90,  616, 4761,(46656), 591638,   9384288, ...];
A^7: [1,  14, 119,  882, 6986, 67214, (823543), 12652712, ...];
A^8: [1,  16, 152, 1216, 9940, 94768, 1126992, (16777216), ...]; ...
where the coefficient of x^n in A(x)^(n+1) equals (n+1)^(n+1).

Prog

(PARI) {a(n)=polcoeff(x/serreverse(x*sum(m=0, n+1, (m+1)^m*x^m)+x^2*O(x^n)), n)}
for(n=0, 20, print1(a(n), ", "))

Crossrefs

Cf. A182957, A180747, A242749.

Sequence in context: A019014 A128595 A358715 * A323299 A111195 A323293

Adjacent sequences: A180746 A180747 A180748 * A180750 A180751 A180752

Keyword

nonn

Author

Paul D. Hanna, Jan 22 2011

Status

approved