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Search: id:A108315
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| A108315 |
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Composite numbers n such that a^v + b^v + c^v + ... is prime, where a*b*c* ... is the prime factorization of n and v is the number of primes dividing n (counted with repetition). |
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+0
1
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| 6, 10, 12, 14, 26, 28, 34, 40, 45, 52, 63, 74, 75, 80, 94, 96, 117, 126, 134, 146, 152, 153, 165, 175, 194, 206, 245, 261, 268, 274, 296, 320, 325, 326, 333, 334, 363, 376, 384, 386, 387, 399, 466, 468, 475, 477, 486, 490, 500, 504, 507, 522, 531, 536, 539, 550
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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5166592 generates a 41 digit prime. Some consecutive terms are (74,75) (152,153) (325,326) ... Conjecture: there are infinitely many consecutive values.
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EXAMPLE
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a(5)=26 because 26=2*13 and 2^2 + 13^2 = 173, a prime.
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CROSSREFS
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Cf. A001222, A082813.
Sequence in context: A028919 A015921 A134620 this_sequence A134616 A081390 A143958
Adjacent sequences: A108312 A108313 A108314 this_sequence A108316 A108317 A108318
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KEYWORD
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easy,nonn
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AUTHOR
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Jason Earls (zevi_35711(AT)yahoo.com), Jun 30 2005
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