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A117495
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Product of a prime number p and the number of primes smaller than p.
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1
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0, 3, 10, 21, 44, 65, 102, 133, 184, 261, 310, 407, 492, 559, 658, 795, 944, 1037, 1206, 1349, 1460, 1659, 1826, 2047, 2328, 2525, 2678, 2889, 3052, 3277, 3710, 4061, 4384, 4587, 5066, 5285, 5652, 6031, 6346, 6747, 7160, 7421, 8022, 8299, 8668, 8955, 9706
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OFFSET
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1,2
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LINKS
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Table of n, a(n) for n=1..47.
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FORMULA
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a(n) = (n-1)*prime(n). [From Zak Seidov, Aug 15 2010]
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EXAMPLE
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a(9)=184 because (1) the 9th prime number is 23, (2)there are 8 primes smaller than 23 and (3)23*8=184
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MAPLE
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with (numtheory):a:=n->sum(ithprime(n), j=2..n):seq(a(n), n=1..47); [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Aug 24 2008]
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MATHEMATICA
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Table[(n - 1)Prime[n], {n, 60}] [From Zak Seidov, Aug 15 2010]
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CROSSREFS
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Cf. A000720, A036689.
Sequence in context: A038347 A210980 A207380 * A007687 A192033 A006308
Adjacent sequences: A117492 A117493 A117494 * A117496 A117497 A117498
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KEYWORD
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nonn
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AUTHOR
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Luc Stevens (lms022(AT)yahoo.com), Apr 25 2006
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STATUS
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approved
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