A171528 - OEIS

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A171528

Denominator of (n-th composite/n).

1, 1, 3, 4, 1, 1, 1, 8, 9, 5, 11, 4, 13, 7, 3, 8, 17, 9, 19, 5, 7, 11, 23, 2, 25, 2, 27, 2, 29, 2, 31, 2, 33, 17, 35, 9, 37, 38, 39, 40, 41, 7, 43, 44, 45, 46, 47, 12, 49, 5, 17, 26, 53, 27, 5, 28, 57, 58, 59, 5, 61, 31, 21, 8, 13, 66, 67, 68, 69, 14

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

OFFSET

1,3

COMMENTS

Denominator of (A002808(n)/n).

LINKS

Table of n, a(n) for n=1..70.

PROG

(PARI) lista(nn) = {compo = select(n->(! isprime(n) && (n != 1)), vector(nn, i, i)); for (i = 1, #compo, print1(denominator(compo[i]/i), ", "); ); } \\ Michel Marcus, Sep 11 2013

CROSSREFS

Cf. A171527.

Sequence in context: A215202 A139344 A137925 * A299924 A131107 A046547

Adjacent sequences: A171525 A171526 A171527 * A171529 A171530 A171531

KEYWORD

nonn,frac

AUTHOR

Jaroslav Krizek, Dec 11 2009

EXTENSIONS

More terms from Michel Marcus, Sep 11 2013

STATUS

approved