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A079169 revision #8

A079169

Difference between A079168(n) and A079167(n).

0, 0, 0, 0, 0, 2, 0, 0, 0, 2, 0, 2, 0, 2, 2, 0, 0, 4, 0, 2, 2, 2, 0, 2, 0, 2, 0, 2, 0, 8, 0, 0, 2, 2, 2, 4, 0, 2, 2, 2, 0, 8, 0, 2, 2, 2, 0, 2, 0, 4, 2, 2, 0, 6, 2, 2, 2, 2, 0, 8, 0, 2, 2, 0, 2, 8, 0, 2, 2, 8, 0, 4, 0, 2, 4, 2, 2, 8, 0, 2, 0, 2, 0, 8, 2, 2, 2, 2, 0, 10, 2, 2, 2, 2, 2, 2, 0, 4, 2, 4, 0, 8, 0, 2, 8, 2

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,6

LINKS

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

EXAMPLE

a(10) = A079168(10) - A079167(10) = 5-3 = 2.

PROG

(PARI) weightedroundness(n)=local(f, fl, s); f=factor(n); fl=length(f[, 1]); s=0; for (i=1, fl, s=s+i*f[, 2][i]); s alias(wr, weightedroundness) weightedroundness2(n)=local(f, fl, s); f=factor(n); fl=length(f[, 1]); s=0; for (i=1, fl, s=s+i^2*f[, 2][i]); s alias(wr2, weightedroundness2) for (j=2, 500, print1(wr2(j)-wr(j)", "))

CROSSREFS

Cf. A079167, A079168, A001222.

Sequence in context: A321516 A172246 A087893 * A345060 A097106 A175801

Adjacent sequences: A079166 A079167 A079168 * A079170 A079171 A079172

KEYWORD

nonn

AUTHOR

Jon Perry, Dec 31 2002

EXTENSIONS

a(1) = 0 prepended by Antti Karttunen, May 31 2017

STATUS

approved