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A110637
Every 4th term of A083948 where the self-convolution 4th power is congruent modulo 16 to A083948, which consists entirely of numbers 1 through 8.
2
1, 2, 7, 4, 3, 2, 1, 8, 6, 6, 6, 4, 4, 2, 8, 8, 7, 6, 8, 6, 8, 6, 7, 8, 3, 4, 3, 6, 3, 8, 1, 4, 4, 8, 3, 6, 6, 2, 5, 8, 1, 4, 6, 4, 6, 6, 1, 8, 1, 6, 5, 8, 4, 4, 8, 4, 5, 8, 5, 2, 4, 8, 6, 4, 5, 2, 8, 8, 7, 4, 6, 4, 5, 8, 6, 8, 6, 4, 5, 4, 8, 4, 4, 4, 7, 8, 4, 2, 1, 8, 3, 4, 7, 2, 7, 8, 4, 6, 6, 4, 8, 6, 7, 6, 4
OFFSET
0,2
EXAMPLE
A(x) = 1 + 2*x + 7*x^2 + 4*x^3 + 3*x^4 + 2*x^5 + x^6 +...
A(x)^4 = 1 + 8*x + 52*x^2 + 216*x^3 + 754*x^4 + 2008*x^5 +...
A(x)^4 (mod 16) = 1 + 8*x + 4*x^2 + 8*x^3 + 2*x^4 + 8*x^5 +...
G(x) = 1 + 8*x + 4*x^2 + 8*x^3 + 2*x^4 + 8*x^5 + 4*x^6 +...
where G(x) is the g.f. of A083948.
PROG
(PARI) {a(n)=local(d=4, m=8, 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