A110643 Every 2nd term of A083950 where the self-convolution 2nd power is congruent modulo 4 to A083950, which consists entirely of numbers 1 through 10.

1, 5, 10, 5, 10, 3, 5, 10, 10, 10, 5, 5, 5, 5, 5, 8, 10, 10, 5, 10, 7, 10, 5, 10, 5, 7, 5, 5, 10, 10, 7, 10, 10, 5, 5, 9, 5, 5, 5, 10, 8, 10, 10, 10, 10, 8, 5, 5, 10, 10, 5, 10, 10, 10, 5, 6, 5, 5, 10, 5, 10, 10, 5, 10, 10, 1, 5, 5, 10, 10, 5, 5, 5, 10, 5, 5, 10, 5, 5, 10, 4, 10, 10, 5, 5, 6, 10

Offset

0,2

Links

Table of n, a(n) for n=0..86.

Example

A(x) = 1 + 5*x + 10*x^2 + 5*x^3 + 10*x^4 + 3*x^5 + 5*x^6 +...
A(x)^2 = 1 + 10*x + 45*x^2 + 110*x^3 + 170*x^4 + 206*x^5 +...
A(x)^2 (mod 4) = 1 + 2*x + x^2 + 2*x^3 + 2*x^4 + 2*x^5 +...
G(x) = 1 + 10*x + 5*x^2 + 10*x^3 + 10*x^4 + 2*x^5 + 5*x^6 +...
where G(x) is the g.f. of A083950.

Prog

(PARI) {a(n)=local(d=2, m=10, 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

Cf. A083950, A110641, A110642.

Sequence in context: A262922 A276652 A137404 * A010721 A046795 A337545

Adjacent sequences: A110640 A110641 A110642 * A110644 A110645 A110646

Keyword

nonn

Author

Robert G. Wilson v and Paul D. Hanna, Aug 30 2005

Status

approved