A103853 Numbers n such that the string 1000n is the decimal expansion of a prime number.

7, 9, 19, 43, 49, 57, 69, 117, 121, 133, 151, 159, 171, 183, 187, 193, 199, 211, 213, 231, 249, 253, 273, 289, 291, 303, 313, 333, 357, 367, 381, 393, 397, 403, 409, 423, 427, 429, 453, 457, 507, 537, 541, 547, 577, 579, 589, 609, 619, 621, 639, 651, 667

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Example

7 is in the sequence because 10007 is prime.
49 is in the sequence because 100049 is prime.
187 is in the sequence because 1000187 is prime.

Mathematica

Select[Range[700], PrimeQ[FromDigits[Join[{1, 0, 0, 0}, IntegerDigits[#]]]]&] (* Harvey P. Dale, Oct 03 2011 *)

Prog

(Magma) [ n: n in [1..800] | IsPrime(Seqint(Intseq(n) cat [0, 0, 0, 1])) ]; // Klaus Brockhaus, Feb 02 2011

Crossrefs

Cf. A103601, A103602, A103603.

Sequence in context: A032791 A046257 A074343 * A192160 A139202 A243996

Adjacent sequences: A103850 A103851 A103852 * A103854 A103855 A103856

Keyword

base,nonn

Author

Parthasarathy Nambi, Mar 30 2005

Status

approved