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Search: id:A143049
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| A143049 |
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G.f. satisfies: A(x) = 1 + x*A(-x)^6. |
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+0
4
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| 1, 1, -6, -21, 286, 1281, -20592, -100226, 1749462, 8899086, -162993402, -852079872, 16106878320, 85783258295, -1658113447608, -8950840125828, 175904428301062, 959332126312266, -19096256882857668, -104984591307499239, 2111233112316364434
(list; graph; listen)
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OFFSET
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0,3
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FORMULA
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G.f. satisfies: A(x) = 1 + x*(1 - x*A(x)^6)^6.
G.f. satisfies: [A(x)^7 + A(-x)^7]/2 = [A(x)^6 + A(-x)^6]/2.
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EXAMPLE
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A(x) = 1 + x - 6*x^2 - 21*x^3 + 286*x^4 + 1281*x^5 - 20592*x^6 -++-...
A(x)^6 = 1 + 6*x - 21*x^2 - 286*x^3 + 1281*x^4 + 20592*x^5 - 100226*x^6 -...
A(x)^7 = 1 + 7*x - 21*x^2 - 364*x^3 + 1281*x^4 + 27027*x^5 - 100226*x^6 -...
Note that a bisction of A^7 equals a bisection of A^6.
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PROGRAM
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(PARI) a(n)=local(A=x+x*O(x^n)); for(i=0, n, A=1+x*subst(A, x, -x)^6); polcoeff(A, n)
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CROSSREFS
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Cf. A143045, A143046, A143047, A143048.
Sequence in context: A093775 A058821 A054366 this_sequence A164643 A007594 A012858
Adjacent sequences: A143046 A143047 A143048 this_sequence A143050 A143051 A143052
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KEYWORD
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sign
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AUTHOR
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Paul D. Hanna (pauldhanna(AT)juno.com), Jul 19 2008
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