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A068710 Primes whose digits can be arranged in increasing cyclic order - to form a substring of 123456789012345678901234567890... 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Observe that the digits 0 and 9 do not appear in any 4-digit or 7-digit prime in this sequence. Also note that no 10-digit prime has this form (since the sum of 10 consecutive digits is divisible by 3).

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.)

EXAMPLE

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.

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}]]

CROSSREFS

Cf. A068708, A068709. See A177119 for a different (and finite) version.

Sequence in context: A235110 A048398 A059170 * A120805 A177119 A096265

Adjacent sequences:  A068707 A068708 A068709 * A068711 A068712 A068713

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy and V. P. Singh, Mar 05 2002

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

STATUS

approved

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Last modified September 18 05:32 EDT 2019. Contains 327165 sequences. (Running on oeis4.)