cp's OEIS Frontend

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.

%I A110639 #7 Mar 12 2015 18:52:01
%S A110639 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,
%T A110639 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,
%U A110639 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
%N 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.
%e A110639 A(x) = 1 + x + 9*x^2 + 9*x^3 + 2*x^4 + 7*x^5 + 5*x^6 +...
%e A110639 A(x)^9 = 1 + 9*x + 117*x^2 + 813*x^3 + 5976*x^4 + 33381*x^5 +...
%e A110639 A(x)^9 (mod 27) = 1 + 9*x + 9*x^2 + 3*x^3 + 9*x^4 + 9*x^5 +...
%e A110639 G(x) = 1 + 9*x + 9*x^2 + 3*x^3 + 9*x^4 + 9*x^5 + 3*x^6 +...
%e A110639 where G(x) is the g.f. of A083949.
%o A110639 (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)}
%Y A110639 Cf. A083949, A110640, A110641.
%K A110639 nonn
%O A110639 0,3
%A A110639 _Robert G. Wilson v_ and _Paul D. Hanna_, Aug 30 2005