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A110639
Every 9th term of A083949 where the self-convolution 9th power is congruent modulo 27 to A083949, which consists entirely of numbers 1 through 9.
1
1, 1, 9, 9, 2, 7, 5, 3, 5, 3, 1, 7, 3, 5, 5, 9, 9, 2, 8, 3, 1, 7, 1, 1, 4, 8, 5, 1, 1, 2, 9, 2, 7, 6, 8, 6, 6, 7, 2, 2, 5, 6, 5, 9, 6, 1, 6, 7, 4, 5, 6, 4, 9, 8, 4, 1, 4, 9, 9, 2, 3, 1, 9, 4, 2, 6, 6, 8, 2, 5, 3, 2, 5, 2, 8, 2, 4, 6, 4, 8, 6, 2, 5, 2, 8, 9, 8, 1, 2, 3, 3, 2, 9, 1, 1, 1, 4, 8, 5, 5, 7, 8, 7, 3, 1
OFFSET
0,3
EXAMPLE
A(x) = 1 + x + 9*x^2 + 9*x^3 + 2*x^4 + 7*x^5 + 5*x^6 +...
A(x)^9 = 1 + 9*x + 117*x^2 + 813*x^3 + 5976*x^4 + 33381*x^5 +...
A(x)^9 (mod 27) = 1 + 9*x + 9*x^2 + 3*x^3 + 9*x^4 + 9*x^5 +...
G(x) = 1 + 9*x + 9*x^2 + 3*x^3 + 9*x^4 + 9*x^5 + 3*x^6 +...
where G(x) is the g.f. of A083949.
PROG
(PARI) {a(n)=local(d=9, m=9, A=1+m*x); for(j=2, d*n, for(k=1, m, t=polcoeff((A+k*x^j+x*O(x^j))^(1/m), j); if(denominator(t)==1, A=A+k*x^j; break))); polcoeff(A, d*n)}
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved