A068710 Primes whose digits can be arranged in increasing cyclic order - to form a substring of 123456789012345678901234567890...
2, 3, 5, 7, 23, 43, 67, 89, 109, 809, 1423, 2143, 2341, 2543, 4231, 4253, 4523, 4567, 4657, 5647, 5867, 6547, 6857, 10243, 10289, 10789, 10987, 12043, 12809, 18097, 19087, 20143, 20341, 20431, 20981, 21089, 23041, 24103, 25463, 25643, 28019, 28109, 28901, 30241, 32401, 36457, 40123, 40213, 40231, 41023
Offset: 1
Examples
2143 is a term as its digits can be arranged as 1234. 109 is a terms since the digits can be permuted to give 901.
Links
- T. D. Noe and David Consiglio, Jr., Table of n, a(n) for n = 1..9463 (terms < 5 x 10^7. The 1287 terms < 10^7 were entered by T. D. Noe.)
Programs
-
Mathematica
cyclicP[n_] := Module[{d = Mod[Range[n + 9], 10], ds, u, i}, ds = Partition[d, n, 1]; u = {}; Do[u = Union[u, Select[FromDigits/@Permutations[ds[[i]]], # > 10^(n - 1) && PrimeQ[#] &]], {i, 10}]; u]; Flatten[Table[cyclicP[n], {n, 7}]]
Extensions
Jan 22 2011: There were omissions after the term 6857 (10243 for example), so I deleted the terms beyond this point, and the presumably erroneous Mma program that accompanied them. Thanks to Marco RipĂ for pointing out that there were errors. - N. J. A. Sloane
Corrected by T. D. Noe, Jan 24 2011
Comments