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Search: id:A007468
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| A007468 |
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Sum of next n primes.
(Formerly M1846)
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+0
10
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| 2, 8, 31, 88, 199, 384, 659, 1056, 1601, 2310, 3185, 4364, 5693, 7360, 9287, 11494, 14189, 17258, 20517, 24526, 28967, 33736, 38917, 45230, 51797, 59180, 66831, 75582, 84463, 95290, 106255, 117424, 129945, 143334, 158167, 173828, 190013
(list; graph; listen)
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OFFSET
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1,1
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FORMULA
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a(n)=p(1+n(n-1)/2)+...+p(n+n(n-1)/2), where p(i) is i-th prime.
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EXAMPLE
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a(1)=2 because "sum of next 1 prime" is 2, a(2)=8 because sum of next 2 primes is 3+5=8, a(3)=31 because sum of next 3 primes is 7+11+13=31, etc.
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MATHEMATICA
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a[n_] := Sum[Prime[i], {i, 1+n(n-1)/2, n+n(n-1)/2}]
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CROSSREFS
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Sequence in context: A054662 A036723 A026693 this_sequence A054137 A062456 A077838
Adjacent sequences: A007465 A007466 A007467 this_sequence A007469 A007470 A007471
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KEYWORD
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nonn,easy
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AUTHOR
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njas, Simon Plouffe (plouffe(AT)math.uqam.ca)
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EXTENSIONS
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More terms from Zak Seidov (zakseidov(AT)yahoo.com), Sep 21 2002
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