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A087866 Composition length of the n-th symmetric power of the natural representation of a finite subgroup of SL(2,C) of type E_8 (binary icosahedral group). 1
1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 4, 4, 4, 3, 4, 4, 5, 5, 6, 5, 6, 6, 7, 6, 7, 6, 7, 7, 9, 8, 9, 8, 9, 8, 10, 9, 10, 9, 11, 10, 12, 11, 12, 10, 12, 11, 13, 12, 14, 12, 14, 13, 15, 13, 15, 13, 15, 14, 17, 15, 17, 15, 17, 15, 18, 16, 18, 16, 19, 17, 20, 18, 20, 17, 20, 18, 21, 19, 22, 19 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,7

REFERENCES

Y. Ito, I. Nakamura, Hilbert schemes and simple singularities, New trends in algebraic geometry (Warwick, 1996), 151-233, Cambridge University Press, 1999.

LINKS

Table of n, a(n) for n=0..81.

Index entries for linear recurrences with constant coefficients, signature (1,0,0,0,0,1,-1,0,0,1,-1,0,0,0,0,-1,1)

FORMULA

G.f.: (1-x^15)/((1-x)*(1-x^6)*(1-x^10)).

a(n) = n/60*(15+(-1)^n+b(n)) where b(n) is the 30-periodic sequence {60, 46, 28, 18, -4, -10, 24, 22, -8, -6, 20, 26, 48, 58, 16, -30, -16, 2, 12, 34, 40, 6, 8, 38, 36, 10, 4, -18, -28, 14}. - Benoit Cloitre, Oct 27 2003

MATHEMATICA

CoefficientList[Series[(1-x^15)/((1-x)(1-x^6)(1-x^10)), {x, 0, 100}], x] (* Harvey P. Dale, Jan 20 2019 *)

PROG

(PARI) a(n)=polcoeff((1-x^15)/((1-x)*(1-x^6)*(1-x^10))+O(x^(n+1)), n)

CROSSREFS

Cf. A008651.

Sequence in context: A194292 A308403 A073578 * A061392 A048273 A175387

Adjacent sequences:  A087863 A087864 A087865 * A087867 A087868 A087869

KEYWORD

easy,nonn

AUTHOR

Paul Boddington, Oct 27 2003

EXTENSIONS

More terms from Benoit Cloitre, Oct 27 2003

STATUS

approved

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Last modified March 30 10:26 EDT 2020. Contains 333125 sequences. (Running on oeis4.)