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A110630 Every 2nd term of A083954 such that the self-convolution 2nd power is congruent modulo 8 to A083954, which consists entirely of numbers 1 through 4. 2
1, 2, 3, 4, 1, 4, 3, 4, 3, 4, 2, 2, 4, 4, 3, 2, 2, 2, 3, 2, 3, 2, 4, 2, 2, 4, 2, 4, 2, 2, 1, 4, 1, 2, 4, 4, 1, 2, 3, 4, 4, 4, 3, 4, 2, 2, 2, 2, 1, 4, 1, 2, 3, 2, 4, 4, 1, 4, 1, 4, 2, 2, 3, 4, 2, 4, 2, 4, 3, 4, 4, 2, 4, 2, 1, 2, 4, 4, 4, 4, 1, 2, 4, 4, 2, 2, 3, 4, 1, 2, 2, 4, 1, 2, 4, 4, 3, 2, 3, 4, 1, 4, 4, 4, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..104.

FORMULA

a(n) = A083954(2*n) for n>=0.

EXAMPLE

A(x) = 1 + 2*x + 3*x^2 + 4*x^3 + x^4 + 4*x^5 + 3*x^6 + 4*x^7 +...

A(x)^2 = 1 + 4*x + 10*x^2 + 20*x^3 + 27*x^4 + 36*x^5 + 44*x^6 +...

A(x)^2 (mod 8) = 1 + 4*x + 2*x^2 + 4*x^3 + 3*x^4 + 4*x^5 +...

G083954(x) = 1 + 4*x + 2*x^2 + 4*x^3 + 3*x^4 + 4*x^5 + 4*x^6 +...

where G083954(x) is the g.f. of A083954.

PROG

(PARI) {a(n)=local(d=2, m=4, 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. A083954, A110629.

Sequence in context: A270313 A318308 A003324 * A238883 A325242 A257053

Adjacent sequences:  A110627 A110628 A110629 * A110631 A110632 A110633

KEYWORD

nonn

AUTHOR

Robert G. Wilson v and Paul D. Hanna, Aug 09 2005

STATUS

approved

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Last modified August 20 18:56 EDT 2019. Contains 326154 sequences. (Running on oeis4.)