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A116074
Primes that have the property that deleting some digit results in a prime with the same multiplicative order, or period (repeating length of 1/p).
2
2161, 155801, 263201, 445001, 617801, 755401, 758201, 1142201, 1273001, 1293401, 1352201, 1491001, 1494401, 1628801, 1801601, 2414201, 2447801, 2611001, 2629001, 2876801, 3049801, 3267001, 3422801, 3541801, 3744401, 3759001, 3825401, 3838201, 3871601, 3952601
OFFSET
1,1
EXAMPLE
2161 and 211 (delete a digit from 2161) are both primes with period 30, so 2161 is in the sequence.
MATHEMATICA
pL[n_] := MultiplicativeOrder[10, n]; hQ[n_] := Block[{s, d = IntegerDigits@n, pe}, s = Union@ Select[FromDigits /@ (Delete[d, #] & /@ Range@ Length@d), PrimeQ]; If[s != {}, pe = pL@n; s = Select[s, pe == pL@# &]]; s != {}]; Select[
Prime@ Range[10^5], hQ] (* Giovanni Resta, Jan 06 2014 *)
CROSSREFS
Sequence in context: A061335 A159238 A289725 * A252563 A035872 A126831
KEYWORD
base,nonn
AUTHOR
G. L. Honaker and Jud McCranie, Feb 03 2006
EXTENSIONS
a(5)-a(30) from Giovanni Resta, Jan 06 2014
STATUS
approved