A155053 Primes n with nonprime smallest digit of prime(n).

5, 7, 11, 13, 19, 29, 31, 37, 41, 43, 47, 53, 67, 79, 83, 89, 97, 101, 113, 127, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307, 311, 313, 317, 331, 347, 349, 353, 359, 379, 397, 409, 421, 431, 433, 439, 443, 449, 467, 479, 491, 523, 541, 557, 563, 569, 571, 577, 601, 613, 617, 619, 641, 643, 647, 653, 673, 677, 683, 691, 701, 709, 719, 727, 743, 751, 757, 761, 769

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Example

a(1) = 5 corresponds to the fact that the fifth prime is 11, the smallest digit of which is 1, which is nonprime.
a(2) = 7: the seventh prime is 17, the smallest digit of which is 1, which is nonprime.
a(3) = 11: the eleventh prime is 31, the smallest digit of which is 1, which is, again, nonprime.

Mathematica

Select[Prime[Range[150]], !PrimeQ[Min[IntegerDigits[Prime[#]]]] &] (* Harvey P. Dale, Nov 25 2010 *)

Crossrefs

Cf. A154981.

Sequence in context: A180950 A112397 A081759 * A152468 A267945 A088664

Adjacent sequences: A155050 A155051 A155052 * A155054 A155055 A155056

Keyword

nonn,base,less

Author

Juri-Stepan Gerasimov, Jan 19 2009

Extensions

Corrected (19 inserted, 1673 replaced by 167) by R. J. Mathar, May 05 2010

More terms from Harvey P. Dale, Nov 25 2010

Status

approved