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A179267
Numbers n which divide the periodic part (with zeros at end) of the decimal expansion of 1/n.
1
3, 6, 487, 974, 1461, 2435, 2922, 4383, 4870, 7305, 8766, 12175, 13149, 14610, 17532, 21915, 24350, 26298, 29220, 36525, 43830, 48700, 52596, 65745, 73050, 87660, 109575, 131490, 146100, 219150, 262980, 328725, 438300, 657450, 1095750
OFFSET
1,1
COMMENTS
There are two definitions of the periodic part: zeros may either begin or end the periodic part. For example, for 1/11 = 0.0909090..., the periodic part could be either 09 or 90. This sequences assumes that the zeros are at the end of the periodic part. See A171928 for the case of zeros at the beginning of the periodic part.
Note that the terms following 487 are divisible by 487. This pattern continues until the prime number 56598313, which is another member of A045616.
MATHEMATICA
Reap[Do[k=RealDigits[1/n][[1, -1]]; If[Head[k] === List && Mod[FromDigits[k], n] == 0, Sow[n]], {n, 10000}]][[2, 1]]
CROSSREFS
Sequence in context: A068375 A126297 A157540 * A171928 A308259 A034879
KEYWORD
base,nonn
AUTHOR
T. D. Noe, Jul 06 2010
STATUS
approved