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A109554
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pi(n)[prime(n+1)-prime(n)], where pi(n) is the number of prime numbers less than or equal to n and prime(k) is the k-th prime.
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0
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0, 2, 4, 8, 6, 12, 8, 16, 24, 8, 30, 20, 12, 24, 36, 36, 14, 42, 32, 16, 48, 32, 54, 72, 36, 18, 36, 18, 40, 140, 44, 66, 22, 110, 22, 66, 72, 48, 72, 72, 26, 130, 28, 56, 28, 168, 180, 60, 30, 60, 90, 30, 160, 96, 96, 96, 32, 96, 68, 34, 180, 252, 72, 36, 72, 252, 114, 190, 38
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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EXAMPLE
| a(2)=pi(2)[prime(3)-prime(2)]=1*(5-3)=2.
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MAPLE
| with(numtheory): a:=n->pi(n)*(ithprime(n+1)-ithprime(n)): seq(a(n), n=1..70);
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MATHEMATICA
| a = Table[(Prime[n + 1] - Prime[n])*PrimePi[n], {n, 1, 200}]
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CROSSREFS
| Sequence in context: A121711 A125597 A151732 * A140692 A048640 A124510
Adjacent sequences: A109551 A109552 A109553 * A109555 A109556 A109557
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KEYWORD
| nonn
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AUTHOR
| Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Jun 27 2005
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