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 A090934 Primes such that least significant digit swapped with all other digits yields primes. 1

%I

%S 2,3,5,7,11,13,17,31,37,71,73,79,97,113,131,179,199,311,313,337,373,

%T 733,919,991,1171,1399,1913,3191,3313,3797,3911,9733,11131,11171,

%U 11311,13313,13933,19979,31193,31333,31379,31391,33119,71191,71333,77377

%N Primes such that least significant digit swapped with all other digits yields primes.

%C Only digits 1,3,7 and 9 can be used for terms with more than 1 digit.

%e 179 is a term as 179, 197 & 971 are all prime.

%t fQ[n_] := Block[{a = c = IntegerDigits[n], b = {}, l = Floor[ Log[10, n] + 1]}, Do[ a = c; {a[[ -1]], a[[i]]} = {a[[i]], a [[ -1]]}; AppendTo[b, FromDigits[a]], {i, 1, l}]; Union[ PrimeQ[b]] == {True}]; Select[Prime[ Range[10000]], fQ[ # ] &] (* _Ed Pegg Jr_, Jan 15 2004 *)

%K base,nonn

%O 1,1

%A _Amarnath Murthy_, Dec 29 2003

%E Edited, corrected and extended by _Robert G. Wilson v_, Jan 15 2004

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Last modified January 20 03:25 EST 2022. Contains 350467 sequences. (Running on oeis4.)