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Search: id:A088315
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| A088315 |
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For n such that all numbers between the largest prime preceding n! and the smallest prime following n! + n are composite (see A088331), sequence is number of such consecutive composite numbers. |
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+0
1
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| 5, 13, 7, 11, 53, 29, 21, 29, 89, 19, 89, 75, 89, 77, 189, 59, 61, 103, 185, 203, 189, 95, 167, 253, 107, 187, 79, 37, 289, 173, 257, 43, 169, 135, 175, 179, 155, 291, 189, 311, 155, 141, 157, 449, 119, 129, 349, 131, 609, 383, 391, 429, 409, 839, 201, 371, 425
(list; graph; listen)
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OFFSET
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2,1
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FORMULA
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a(n) = nextprime(A088331(n)!+A088331(n)) - precprime(A088331(n)!) - 1.
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EXAMPLE
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There are 13 consecutive composite numbers between primes 113 < 5! and 127 > 5!+5. 13 is the second entry in the sequence.
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PROGRAM
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(PARI) factgaps2(m) = { for(n=2, m, c=0; f=0; nf=n!; for(x=precprime(nf), nextprime(nf+n), if(isprime(nf+1), f=1; break); if(!isprime(x), c++) ); if(f==0, print1(c", ")) ) }
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CROSSREFS
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Cf. A088331.
Sequence in context: A089619 A094473 A068530 this_sequence A138296 A094474 A064109
Adjacent sequences: A088312 A088313 A088314 this_sequence A088316 A088317 A088318
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KEYWORD
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nonn
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AUTHOR
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Cino Hilliard (hillcino368(AT)gmail.com), Nov 06 2003
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EXTENSIONS
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Edited by Ray Chandler (rayjchandler(AT)sbcglobal.net), Nov 10 2003
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