A263108 Semiprimes m such that the leftward cyclic permutation of its decimal digits is a larger semiprime.

15, 26, 39, 49, 58, 122, 129, 134, 141, 145, 155, 158, 159, 161, 177, 178, 183, 185, 187, 226, 254, 262, 298, 339, 341, 355, 358, 362, 371, 381, 391, 393, 394, 445, 451, 469, 473, 493, 497, 565, 581, 583, 586, 589, 674, 781, 791, 889, 895, 899, 1114, 1119

Offset

1,1

Comments

Subsequence of A263106.

Links

Zak Seidov, Table of n, a(n) for n = 1..28070 (all terms up to 10^6)

Example

Permute the digits of 15 = 3 * 5 to get 51 = 3 * 17.
Permute the digits of 26 = 2 * 13 to get 62 = 2 * 31.
Permute the digits of 122 = 2 * 61 to get 221 = 13 * 17.
Permute the digits of 129 = 3 * 43 to get 291 = 3 * 97.

Mathematica

Select[Range[4, 1000000], 2 == PrimeOmega[#] == PrimeOmega[fd = FromDigits[RotateLeft[IntegerDigits[#]]]] && fd > # &] (* for b-file *)

Crossrefs

Cf. A001292, A001358, A085751, A263106.

Sequence in context: A097393 A050700 A373731 * A274182 A139566 A097963

Adjacent sequences: A263105 A263106 A263107 * A263109 A263110 A263111

Keyword

nonn,base

Author

Zak Seidov, Oct 09 2015

Status

approved