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A008635
Molien series for alternating group Alt_12 (or A_12).
2
1, 1, 2, 3, 5, 7, 11, 15, 22, 30, 42, 56, 77, 100, 133, 172, 224, 285, 366, 460, 582, 725, 905, 1116, 1380, 1686, 2063, 2503, 3036, 3655, 4401, 5262, 6290, 7476, 8877, 10489, 12384, 14552, 17084, 19978, 23334, 27156, 31570, 36578, 42333, 48849
OFFSET
0,3
REFERENCES
D. J. Benson, Polynomial Invariants of Finite Groups, Cambridge, 1993, p. 105.
LINKS
Index entries for linear recurrences with constant coefficients, signature (1, 1, 0, 0, -1, 1, -2, -1, 0, 0, 1, 0, 1, 1, 2, 1, 0, 0, -1, -2, -3, -3, -1, -1, 1, 0, 3, 4, 3, 3, 1, 2, -2, -3, -3, -4, -3, -3, -2, 2, 1, 3, 3, 4, 3, 0, 1, -1, -1, -3, -3, -2, -1, 0, 0, 1, 2, 1, 1, 0, 1, 0, 0, -1, -2, 1, -1, 0, 0, 1, 1, -1).
FORMULA
G.f.: (1+x^66)/((1-x)*(1-x^2)*(1-x^3)*(1-x^4)*(1-x^5)*(1-x^6)*(1-x^7)*(1-x^8)*(1-x^9)*(1-x^10)*(1-x^11)*(1-x^12)).
MAPLE
seq(coeff(series( (1+x^66)/mul((1-x^j), j=1..12)), x, n+1), x, n), n = 0..50); # G. C. Greubel, Feb 02 2020
MATHEMATICA
CoefficientList[Series[(1+x^66)/Product[(1-x^j), {j, 12}], {x, 0, 50}], x] (* G. C. Greubel, Feb 02 2020 *)
PROG
(PARI) Vec( (1+x^66)/prod(j=1, 12, 1-x^j) +O('x^50) ) \\ G. C. Greubel, Feb 02 2020
(Magma) R<x>:=PowerSeriesRing(Integers(), 50); Coefficients(R!( (1+x^66)/(&*[1-x^j: j in [1..12]]) )); // G. C. Greubel, Feb 02 2020
(Sage)
def A008631_list(prec):
P.<x> = PowerSeriesRing(ZZ, prec)
return P( (1+x^66)/product(1-x^j for j in (1..12)) ).list()
A008631_list(70) # G. C. Greubel, Feb 02 2020
CROSSREFS
Sequence in context: A328546 A242697 A218512 * A008641 A341714 A332746
KEYWORD
nonn,easy
EXTENSIONS
More terms from Sean A. Irvine, Apr 01 2018
STATUS
approved