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

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.

Links

Table of n, a(n) for n=1..46.

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

Adjacent sequences: A090931 A090932 A090933 * A090935 A090936 A090937

Keyword

base,nonn

Author

Amarnath Murthy, Dec 29 2003

Extensions

Edited, corrected and extended by Robert G. Wilson v, Jan 15 2004

Status

approved