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A092117 Numbers n such that the concatenation 2n3n5n7n11n13 is prime. 6
10, 43, 51, 55, 58, 60, 136, 171, 204, 213, 214, 222, 270, 288, 309, 334, 339, 364, 366, 376, 414, 423, 460, 477, 492, 501, 502, 507, 513, 519, 565, 585, 586, 597, 621, 649, 726, 729, 787, 852, 861, 870, 903, 906, 915, 933, 946, 981, 988, 1005, 1038, 1071 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This concatenation is fp(6, n) as defined in A083677.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

10 is in the sequence because 210310510710111013 is prime.

MATHEMATICA

v={}; Do[If[PrimeQ[FromDigits[Join[{2}, IntegerDigits[n], {3}, IntegerDigits[n], {5}, IntegerDigits[n], {7}, IntegerDigits[n], {1, 1}, IntegerDigits[n], {1, 3}]]], v=Append[v, n]], {n, 1400}]; v

fp6Q[n_] := PrimeQ[ FromDigits[ Flatten[ IntegerDigits /@ Insert[{2, 3, 5, 7, 11, 13}, n, {{2}, {3}, {4}, {5}, {6}}]]]]; Select[ Range[1100], fp6Q[ # ] &] (* Robert G. Wilson v, Dec 11 2004 *)

Select[Range[1100], PrimeQ[FromDigits[Flatten[IntegerDigits/@Riffle[{2, 3, 5, 7, 11, 13}, #]]]]&] (* Harvey P. Dale, Mar 21 2013 *)

CROSSREFS

Cf. A032711, A083677, A083966, A083677, A092115, A083969.

Sequence in context: A324512 A077541 A084036 * A245663 A244802 A211070

Adjacent sequences:  A092114 A092115 A092116 * A092118 A092119 A092120

KEYWORD

nonn,base

AUTHOR

Farideh Firoozbakht, Jun 15 2003

EXTENSIONS

Edited by N. J. A. Sloane at the suggestion of Andrew S. Plewe, May 27 2007

STATUS

approved

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Last modified October 20 04:37 EDT 2019. Contains 328247 sequences. (Running on oeis4.)