A156976 Primes whose last digit is not a prime but all the other digits are primes.

29, 31, 59, 71, 79, 229, 239, 251, 271, 331, 359, 379, 521, 571, 739, 751, 2221, 2239, 2251, 2339, 2351, 2371, 2521, 2531, 2539, 2551, 2579, 2729, 2731, 3221, 3229, 3251, 3259, 3271, 3329, 3331, 3359, 3371, 3529, 3539, 3559, 3571, 3739, 3779, 5231, 5279

Offset

1,1

Comments

It is obvious that the last digit must be a 1 or 9. It is also obvious that the digits 0, 4, 6, or 8 cannot occur anywhere in the numbers.

Links

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

Chris Caldwell, The First 1,000 Primes

Example

751 is a prime in which the last digit is not a prime but the other digits are primes.

Maple

a := proc (n) local n1, n2, n3: n1 := ithprime(n): n2 := convert(n1, base, 10): n3 := convert(convert(floor((1/10)*n1), base, 10), set): if member(n2[1], {1, 9}) = true and `subset`(n3, {2, 3, 5, 7}) = true then n1 else end if end proc: seq(a(n), n = 1 .. 750); # Emeric Deutsch, Mar 15 2009

Crossrefs

Cf. A000040, A156553.

Sequence in context: A132240 A132243 A125523 * A157681 A288615 A158342

Adjacent sequences: A156973 A156974 A156975 * A156977 A156978 A156979

Keyword

base,nonn

Author

Parthasarathy Nambi, Feb 19 2009

Extensions

More terms from Emeric Deutsch, Mar 15 2009

Status

approved