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A075674
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Sum of next n odd interprimes.
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3
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9, 36, 153, 378, 805, 1576, 2733, 3818, 5857, 8006, 10537, 14812, 19389, 23472, 29757, 36416, 44067, 52274, 61307, 71740, 86195, 104056, 120463, 138128, 158209, 181160, 205973, 229728, 255013, 281608
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OFFSET
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1,1
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COMMENTS
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Sum of next n primes in A007468. Sum of next n integer interprimes in A075673. Sum of next n even interprimes in A075675.
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LINKS
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EXAMPLE
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a(1) = (7+11)/2 = 9; a(2) = (13+17)/2+(19+23)/2 = 15 + 21 = 36.
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MATHEMATICA
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(* sum of next n odd interprimes*) od=Select[Table[(Prime[i]+Prime[i+1])/2, {i, 2, 2000}], OddQ]; i1 := n(n-1)/2+1; i2 := n(n-1)/2+n; A075674=Table[Sum[od[[i]], {i, i1, i2}], {n, 30}]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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