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Search: id:A082244
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| A082244 |
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Smallest odd prime that is the sum of 2n+1 consecutive primes. |
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+0
2
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| 3, 23, 53, 197, 127, 233, 691, 379, 499, 857, 953, 1151, 1259, 1583, 2099, 2399, 2417, 2579, 2909, 3803, 3821, 4217, 4651, 5107, 5813, 6829, 6079, 6599, 14153, 10091, 8273, 10163, 9521, 12281, 13043, 11597, 12713, 13099, 16763, 15527, 16823, 22741
(list; graph; listen)
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OFFSET
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0,1
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FORMULA
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The sum of the reciprocals = 0.4304...
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EXAMPLE
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For n = 2,
2+3+5+7+11=28
3+5+7+11+13=39
5+7+11+13+17=53
so 53 is the first prime that is the sum of 5 consecutive primes
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PROGRAM
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(PARI) \ First prime that the sum of an odd number of consecutive primes psumprm(n) = { sr=0; forstep(i=1, n, 2, s=0; for(j=1, i, s+=prime(j); ); for(x=1, n, s = s - prime(x)+ prime(x+i); if(isprime(s), sr+=1.0/s; print1(s" "); break); ); ); print(); print(sr) }
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CROSSREFS
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See A070934 for another version.
Adjacent sequences: A082241 A082242 A082243 this_sequence A082245 A082246 A082247
Sequence in context: A107169 A032003 A031907 this_sequence A143853 A141047 A003531
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KEYWORD
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easy,nonn
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AUTHOR
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Cino Hilliard (hillcino368(AT)gmail.com), May 09 2003
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