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A153055
Numbers n such that the binary expansion of n is a substring of the binary expansion of 1/n.
2
11, 13, 27, 29, 45, 53, 54, 59, 61, 79, 83, 101, 103, 106, 109, 115, 121, 125, 155, 158, 163, 166, 173, 181, 187, 199, 202, 206, 211, 212, 213, 218, 237, 251, 310, 326, 329, 345, 346, 362, 369, 377, 393, 398, 407, 409, 412, 422, 436, 441, 459, 563, 575, 581
OFFSET
1,1
EXAMPLE
a(2) = 13 because bin(13)=1101 and bin(1/13)=.000100111011(repeats infinitely) and 1101 appears in the binary expansion of the reciprocal.
CROSSREFS
Sequence in context: A374059 A022325 A295340 * A146915 A067786 A132245
KEYWORD
base,easy,nonn
AUTHOR
Gil Broussard, Dec 17 2008
STATUS
approved