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A090933 Primes such that most significant digit swapped with all other digits yields primes. 0

%I

%S 2,3,5,7,11,13,17,31,37,71,73,79,97,101,107,113,131,149,167,179,181,

%T 191,199,311,337,373,389,701,709,727,733,739,751,757,787,797,907,919,

%U 937,941,953,991,1009,1013,1031,1049,1051,1091,1123,1181,1319,1321,1381

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

%C Appears to be denser than A090934, where the least significant digit is swapped.

%e 149 is a term as 149, 419 & 491 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[ 270]], fQ[ # ] &] (* _Ed Pegg Jr_, Jan 15 2004 *)

%Y Cf. A090934.

%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 24 19:03 EST 2022. Contains 350565 sequences. (Running on oeis4.)