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A146982 Numbers n such that Product{i=1..n}[sigma_0(i)] / n is an integer. 0
1, 2, 4, 6, 8, 9, 12, 16, 18, 20, 24, 27, 30, 32, 36, 40, 45, 48, 50, 54, 60, 64, 70, 72, 75, 80, 81, 84, 90, 96, 100, 105, 108, 112, 120, 125, 126, 128, 135, 140, 144, 150, 160, 162, 168, 175, 180, 189, 192, 196, 200, 210, 216, 224, 225, 240, 243, 245, 250, 252, 256 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

A066843(n)/A000027(n) is an integer.

PROG

(MAGMA) [ n: n in [1..260] | &*[ NumberOfDivisors(k): k in [1..n] ] mod n eq 0 ]; [From Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Nov 05 2008]

CROSSREFS

Cf. A066843, A000005, A000027,

Sequence in context: A071562 A100345 A118363 * A090958 A074901 A189294

Adjacent sequences:  A146979 A146980 A146981 * A146983 A146984 A146985

KEYWORD

nonn

AUTHOR

Ctibor O. Zizka (c.zizka(AT)email.cz), Nov 04 2008

EXTENSIONS

Extended beyond a(12) by Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Nov 05 2008

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Last modified February 15 12:24 EST 2012. Contains 205785 sequences.