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A128039
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Numbers n such that 1 - Sum{k=1..n-1}A001223(k)*(-1)^k = 0.
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2
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3, 6, 10, 13, 18, 26, 29, 218, 220, 223, 491, 535, 538, 622, 628, 3121, 3126, 3148, 3150, 3155, 3159, 4348, 4436, 4440, 4444, 4458, 4476, 4485, 4506, 4556, 4608, 4611, 4761, 5066, 5783, 5788, 12528, 1061290, 2785126, 2785691, 2867466, 2867469, 2872437
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OFFSET
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1,1
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COMMENTS
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Sequence has 294 terms < 10^7. Being prime(n) = 3 + 2*(Sum{k=1..n-1}A000040(k)*(-1)^k)), for n odd and, prime(n) =(3 + 2*(Sum{k=1..n-1}A000040(k)*(-1)^k)))*(-1), for n even
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LINKS
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EXAMPLE
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MATHEMATICA
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S=0; a=0; Do[S=S+((Prime[k+1]-Prime[k])*(-1)^k); If[1-S==0, a++; Print[a, " ", k+1]], {k, 1, 10^7, 1}]
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CROSSREFS
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Cf. A127596, A001223 (differences between consecutive primes), A000101 (increasing gaps between primes, upper end), A002386 (increasing gaps between primes, lower end), A066033.
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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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