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A061120
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Compute sum of divisors of the p(n+1)-p(n)-1 composite numbers between two consecutive primes; choose the smallest.
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2
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7, 12, 13, 28, 24, 39, 32, 31, 72, 48, 56, 96, 72, 57, 72, 168, 84, 96, 195, 96, 121, 108, 112, 156, 216, 162, 280, 152, 133, 176, 160, 288, 168, 372, 192, 192, 252, 183, 240, 546, 216, 508, 294, 468, 240, 252, 342, 560, 384, 288, 744, 280, 288, 304, 324, 720
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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LINKS
| Harry J. Smith, Table of n, a(n) for n=0,...,1000
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FORMULA
| a(n)=Min{sigma(c); p(n+1)>c>p(n)}, c is composite, p(n) is the n-th prime and sigma=A000203()
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PROG
| (PARI) { n=-1; q=3; m=10^6; forprime (p=5, prime(1003), a=m; for (i=q + 1, p - 1, a=min(sigma(i), a)); q=p; write("b061120.txt", n++, " ", a) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Jul 18 2009]
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CROSSREFS
| A000203, A061141.
Sequence in context: A048653 A205807 A075696 * A078835 A173417 A031021
Adjacent sequences: A061117 A061118 A061119 * A061121 A061122 A061123
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KEYWORD
| nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), May 29 2001
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