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A171527
Numerator of (n-th composite/n).
4
4, 3, 8, 9, 2, 2, 2, 15, 16, 9, 20, 7, 22, 12, 5, 13, 27, 14, 30, 8, 11, 17, 35, 3, 38, 3, 40, 3, 44, 3, 46, 3, 49, 25, 51, 13, 54, 55, 56, 57, 58, 10, 62, 63, 64, 65, 66, 17, 69, 7, 24, 37, 75, 38, 7, 39, 80, 81, 82, 7, 85, 43, 29, 11, 18, 91, 92, 93, 94, 19, 96, 49, 99, 50, 34, 26, 15, 53, 108
OFFSET
1,1
COMMENTS
Numerator of (A002808(n)/n).
LINKS
MAPLE
compos:= remove(isprime, [$2..1300]):
seq(numer(compos[n]/n), n=1..1000); # Robert Israel, Nov 03 2020
MATHEMATICA
Module[{nn=200, cmps, len}, cmps=Select[Range[nn], CompositeQ]; len= Length[ cmps]; #[[1]]/#[[2]]&/@Thread[{cmps, Range[len]}]]//Numerator (* Harvey P. Dale, Jan 08 2022 *)
PROG
(PARI) lista(nn) = {compo = select(n->(! isprime(n) && (n != 1)), vector(nn, i, i)); for (i = 1, #compo, print1(numerator(compo[i]/i), ", "); ); } \\ Michel Marcus, Sep 11 2013
CROSSREFS
Cf. A171528.
Sequence in context: A134390 A004125 A137924 * A240969 A198576 A368551
KEYWORD
nonn,frac,look
AUTHOR
Jaroslav Krizek, Dec 11 2009
EXTENSIONS
More terms from Michel Marcus, Sep 11 2013
Corrected by Robert Israel, Nov 03 2020
STATUS
approved