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A102249 Numbers n such that n1111 is prime. 1
10, 13, 31, 36, 51, 57, 61, 69, 72, 78, 79, 90, 91, 97, 117, 120, 127, 129, 135, 138, 153, 156, 166, 174, 183, 184, 189, 201, 205, 210, 222, 225, 226, 234, 237, 240, 241, 244, 252, 261, 265, 273, 276, 280, 285, 292, 304, 306, 309, 318, 322, 325, 327, 337, 345 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..55.

EXAMPLE

At n=10, n1111 = 101111 (prime).

At n=90, n1111 = 901111 (prime).

At n=138, n1111 = 1381111 (prime).

MATHEMATICA

Select[ Range[ 350], PrimeQ[ FromDigits[ Flatten[ IntegerDigits /@ { #, 1, 1, 1, 1}]]] &] (* Robert G. Wilson v, Feb 21 2005 *)

CROSSREFS

Cf. A024912.

Sequence in context: A126973 A220045 A101215 * A195313 A219829 A062370

Adjacent sequences:  A102246 A102247 A102248 * A102250 A102251 A102252

KEYWORD

nonn,base

AUTHOR

Parthasarathy Nambi, Feb 18 2005

EXTENSIONS

More terms from Robert G. Wilson v, Feb 21 2005

STATUS

approved

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Last modified November 17 08:15 EST 2018. Contains 317275 sequences. (Running on oeis4.)