login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A370437
Expansion of g.f. A(x) satisfying A( x*(1 + 2*x)*A(x) )^3 = A( x^2*(1 + 3*x)*A(x) )^2.
5
1, 0, -3, 10, -15, 84, -161, -174, 612, 1596, 1926, -38592, -5895, 234684, 603621, -2907414, -7559802, 15762420, 116671738, -95405184, -1326191061, -582470792, 14912006205, 21762765822, -142157118077, -418666482912, 1222704927801, 6161408393758, -7256289555369, -80123028681972
OFFSET
1,3
LINKS
EXAMPLE
G.f.: A(X) = x - 3*x^3 + 10*x^4 - 15*x^5 + 84*x^6 - 161*x^7 - 174*x^8 + 612*x^9 + 1596*x^10 + 1926*x^11 - 38592*x^12 - 5895*x^13 + 234684*x^14 + 603621*x^15 + ...
where A( x*(1 + 2*x)*A(x) )^3 = A( x^2*(1 + 3*x)*A(x) )^2.
RELATED SERIES.
B(x) = A( x*(1 + 2*x)*A(x) )^(1/2) = A( x^2*(1 + 3*x)*A(x) )^(1/3)
where B(x) is the g.f. of A370438, which begins
B(x) = x + x^2 - 2*x^3 + 4*x^4 - 5*x^5 + 31*x^6 - 45*x^7 - 57*x^8 - 66*x^9 + 1124*x^10 + 116*x^11 - 8314*x^12 - 21328*x^13 + 76424*x^14 + 229013*x^15 + ...
B(x)^2 = A( x*(1 + 2*x)*A(x) ) = x^2 + 2*x^3 - 3*x^4 + 4*x^5 + 2*x^6 + 36*x^7 + 8*x^8 - 368*x^9 + 207*x^10 + 1674*x^11 + 3699*x^12 - 23640*x^13 - 51605*x^14 + 134174*x^15 + ...
B(x)^3 = A( x^2*(1 + 3*x)*A(x) ) = x^3 + 3*x^4 - 3*x^5 + x^6 + 15*x^7 + 39*x^8 + 88*x^9 - 684*x^10 + 36*x^11 + 3514*x^12 + 6807*x^13 - 33825*x^14 - 124742*x^15 + 217842*x^16 + ...
B(x)^6 = A( x*(1 + 2*x)*A(x) )^3 = x^6 + 6*x^7 + 3*x^8 - 16*x^9 + 45*x^10 + 162*x^11 + 321*x^12 - 1044*x^13 - 4257*x^14 + 12694*x^15 + 37275*x^16 - 61476*x^17 - 530776*x^18 + ...
PROG
(PARI) {a(n) = my(A=[1]); for(i=1, n, A = concat(A, 0); Ax = x*Ser(A);
A[#A] = polcoeff( subst(Ax, x, x^2*(1 + 3*x)*Ax )^2 - subst(Ax, x, x*(1 + 2*x)*Ax )^3, #A+5); ); A[n]}
for(n=1, 30, print1(a(n), ", "))
CROSSREFS
Cf. A370438, A370537 (dual), A370535.
Sequence in context: A037345 A217278 A175336 * A259877 A182334 A051420
KEYWORD
sign
AUTHOR
Paul D. Hanna, Mar 07 2024
STATUS
approved