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A193350 Sum of even divisors of tau(n). 2
0, 2, 2, 0, 2, 6, 2, 6, 0, 6, 2, 8, 2, 6, 6, 0, 2, 8, 2, 8, 6, 6, 2, 14, 0, 6, 6, 8, 2, 14, 2, 8, 6, 6, 6, 0, 2, 6, 6, 14, 2, 14, 2, 8, 8, 6, 2, 12, 0, 8, 6, 8, 2, 14, 6, 14, 6, 6, 2, 24, 2, 6, 8, 0, 6, 14, 2, 8, 6, 14, 2, 24, 2, 6, 8, 8, 6, 14, 2, 12, 0, 6, 2, 24, 6, 6, 6, 14, 2, 24, 6, 8, 6, 6, 6, 24, 2, 8, 8, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A146076(A000005(n)). - Antti Karttunen, May 28 2017

EXAMPLE

a(24) = 14 because tau(24) = 8 and the sum of the 3 even divisors {2, 4, 8} is 14.

MATHEMATICA

Table[Total[Select[Divisors[DivisorSigma[0, n]], EvenQ[ # ]&]], {n, 74}]

PROG

(PARI) a(n)=sumdiv(sigma(n, 0), d, (1-d%2)*d);

CROSSREFS

Cf. A000005, A146076, A193347.

Cf. A000290 (the positions of zeros).

Sequence in context: A008281 A094671 A202015 * A021458 A279741 A099064

Adjacent sequences:  A193347 A193348 A193349 * A193351 A193352 A193353

KEYWORD

nonn

AUTHOR

Michel Lagneau, Jul 23 2011

EXTENSIONS

Data section extended to 100 terms by Antti Karttunen, May 28 2017

STATUS

approved

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Last modified January 25 04:12 EST 2022. Contains 350565 sequences. (Running on oeis4.)