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A035202 Coefficients in expansion of Dirichlet series Product_p (1-(Kronecker(m,p)+1)*p^(-s)+Kronecker(m,p)*p^(-2s))^(-1) for m = 20. 2
1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 2, 0, 0, 0, 0, 1, 0, 1, 2, 1, 0, 2, 0, 0, 1, 0, 0, 0, 2, 0, 2, 1, 0, 0, 0, 1, 0, 2, 0, 1, 2, 0, 0, 2, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 2, 0, 0, 2, 2, 0, 2, 2, 0, 1, 0, 0, 0, 0, 0, 0, 2, 1, 0, 0, 0, 2, 0, 0, 2, 1, 1, 2, 0, 0, 0, 0, 0, 2, 2, 1, 0, 0, 0, 0, 2, 0, 0, 1, 2, 1, 2, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,11

COMMENTS

Also number of divisors of n which end in 1 or 9 minus number of divisors of n which end in 3 or 7. E.g. a(98)=2-1=1 since divisors of 98 are: 1 and 49 counting +1 each; 2, 14 and 98 counting 0 each; and 7 counting -1. - Henry Bottomley, Jul 08 2003

LINKS

Table of n, a(n) for n=1..105.

MathNerds, An Excess of Divisors.

MAPLE

a:= proc(n) local D, d; D:= map(`modp`, convert(numtheory:-divisors(n), list), 10);

      numboccur(1, D) + numboccur(9, D) - numboccur(3, D) - numboccur(7, D);

end proc:

seq(a(n), n=1..1000); # Robert Israel, Sep 22 2014

PROG

(PARI) m=20; direuler(p=2, 101, 1/(1-(kronecker(m, p)*(X-X^2))-X))

CROSSREFS

Cf. A083911, A083913, A083917, A083919.

Sequence in context: A188171 A330733 A328496 * A227835 A281154 A245536

Adjacent sequences:  A035199 A035200 A035201 * A035203 A035204 A035205

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Henry Bottomley, Jul 08 2003

STATUS

approved

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Last modified September 18 12:35 EDT 2021. Contains 347527 sequences. (Running on oeis4.)