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A090934
Primes such that least significant digit swapped with all other digits yields primes.
1
2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, 97, 113, 131, 179, 199, 311, 313, 337, 373, 733, 919, 991, 1171, 1399, 1913, 3191, 3313, 3797, 3911, 9733, 11131, 11171, 11311, 13313, 13933, 19979, 31193, 31333, 31379, 31391, 33119, 71191, 71333, 77377
OFFSET
1,1
COMMENTS
Only digits 1,3,7 and 9 can be used for terms with more than 1 digit.
EXAMPLE
179 is a term as 179, 197 & 971 are all prime.
MATHEMATICA
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 *)
CROSSREFS
Sequence in context: A090933 A107845 A234901 * A068652 A003459 A276132
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Dec 29 2003
EXTENSIONS
Edited, corrected and extended by Robert G. Wilson v, Jan 15 2004
STATUS
approved