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A084433
Numbers all whose cyclic permutations have GCD > 1.
3
2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 15, 18, 20, 21, 22, 24, 26, 27, 28, 30, 33, 36, 39, 40, 42, 44, 45, 46, 48, 50, 51, 54, 55, 57, 60, 62, 63, 64, 66, 68, 69, 70, 72, 75, 77, 78, 80, 81, 82, 84, 86, 87, 88, 90, 93, 96, 99, 102, 105, 108, 111, 114, 117, 120, 123, 126, 129, 132
OFFSET
1,1
COMMENTS
Following are members of this sequence: (1) Numbers made up of even digits (GCD >= 2). (2) Numbers with sum of digits a multiple of 3 (GCD >= 3). (3) Multiples of 11 containing an even number of nonzero digits (GCD >= 11); (i) with highest common factor 11 e.g. 1243; (ii) with highest common factor > 11 e.g. 142857. (4) Numbers made up of identical digits >1 (GCD = the number itself).
LINKS
EXAMPLE
1243 and its cyclic permutations 1243, 2431, 4312, 3124 are members as all are divisible by 11.
148, 481 and 814 are members because their GCD is 37.
CROSSREFS
Sequence in context: A256476 A154771 A071249 * A084434 A034709 A178158
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Jun 02 2003
EXTENSIONS
Corrected and extended by David Wasserman, Dec 28 2004
STATUS
approved