A093438 Least distinct prime p such that p-1 has the prime signature of n, or 0 if no such prime exists.

2, 3, 0, 5, 0, 7, 0, 0, 0, 11, 0, 13, 0, 23, 47, 17, 0, 19, 0, 29, 59, 83, 0, 41, 0, 107, 0, 53, 0, 31, 0, 0, 167, 179, 227, 37, 0, 263, 347, 89, 0, 43, 0, 149, 173, 359, 0, 113, 0, 269, 383, 293, 0, 137, 467, 233, 479, 503, 0, 61, 0, 563, 317, 0, 587, 67, 0, 389, 719, 71, 0, 73, 0

Offset

1,1

Comments

a(n) = 0 for prime n > 2.

Links

Table of n, a(n) for n=1..73.

Example

a(14) = 23 as 23-1 = 22 = 11*2 has the same prime signature p*q, 14 = 2*7.

Crossrefs

Cf. A093439.

Sequence in context: A061397 A331045 A331044 * A375548 A211396 A331097

Adjacent sequences: A093435 A093436 A093437 * A093439 A093440 A093441

Keyword

nonn

Author

Amarnath Murthy, Apr 01 2004

Extensions

Corrected and extended by Rick L. Shepherd, Jun 17 2004

Status

approved