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A106227 Self-convolution 7th power equals A106226, which consists entirely of digits {0,1,2,3,4,5,6} after the initial terms {1,7}. 2
1, 1, -3, 13, -65, 351, -1989, 11650, -69900, 427167, -2648438, 16612947, -105215448, 671760933, -4318468133, 27926126547, -181520036139, 1185220461607, -7769787811032, 51117085986564, -337373170566291, 2233091754693676, -14819626688607761, 98582852441111688 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..23.

EXAMPLE

A(x) = 1 + x - 3*x^2 + 13*x^3 - 65*x^4 + 351*x^5 - 1989*x^6 +-...

A(x)^7 = 1 + 7*x + x^7 + 4*x^14 + 6*x^21 + 5*x^28 + x^35 + 6*x^42 +...

A106226 = {1,7,0,0,0,0,0,1,0,0,0,0,0,0,4,0,0,0,0,0,0,6,...}.

PROG

(PARI) {a(n)=local(A=1+7*x); if(n==0, 1, for(j=1, n, for(k=0, 6, t=polcoeff((A+k*x^j+x*O(x^j))^(1/7), j); if(denominator(t)==1, A=A+k*x^j; break))); return(polcoeff((A+x*O(x^n))^(1/7), n)))}

CROSSREFS

Cf. A106226, A106219, A106221, A106223, A106225.

Sequence in context: A074537 A284714 A200475 * A256332 A284715 A186577

Adjacent sequences:  A106224 A106225 A106226 * A106228 A106229 A106230

KEYWORD

sign,base

AUTHOR

Paul D. Hanna, May 01 2005

STATUS

approved

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Last modified February 20 19:36 EST 2020. Contains 332084 sequences. (Running on oeis4.)