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A093438
Least distinct prime p such that p-1 has the prime signature of n, or 0 if no such prime exists.
1
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.
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
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Apr 01 2004
EXTENSIONS
Corrected and extended by Rick L. Shepherd, Jun 17 2004
STATUS
approved