A090146 - OEIS

A090146

Primes of the form identical digits followed by a 3.

3, 13, 23, 43, 53, 73, 83, 113, 223, 443, 773, 883, 11113, 77773, 88883, 444443, 22222223, 55555553, 88888883, 111111113, 444444443, 777777773, 888888883, 11111111113, 22222222223, 444444444443, 777777777773, 777777777777773, 888888888888883, 777777777777777777773, 111111111111111111111113, 55555555555555555555555553

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OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..60

MATHEMATICA

Select[ FromDigits /@ Flatten[ Table[ PadLeft[{3}, i, # ] & /@ {1, 2, 3, 4, 5, 6, 7, 8, 9}, {i, 2, 18}], 1], PrimeQ[ # ] &]

Union[Flatten[Table[Select[FromDigits/@Table[Join[Table[n, {i}], {3}], {i, 0, 25}], PrimeQ], {n, 9}]]] (* Harvey P. Dale, Nov 25 2010 *)

CROSSREFS

Sequence in context: A178825 A147473 A030431 * A348559 A133313 A230026

Adjacent sequences: A090143 A090144 A090145 * A090147 A090148 A090149

KEYWORD

nonn,base

AUTHOR

Robert G. Wilson v, Nov 22 2003

EXTENSIONS

Additional terms from Harvey P. Dale, Nov 25 2010

STATUS

approved