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A092945
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Group the natural numbers so that the n-th group contains n numbers whose sum as well as the group product + 1 is prime. Sequence contains the last term of each group.
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9
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2, 4, 10, 9, 23, 28, 29, 47, 115, 71, 88, 214, 215, 188, 341, 133, 220, 372, 250, 321, 227, 311, 281, 310, 592, 857, 691, 406, 470, 483, 904, 903, 707, 601, 876, 727, 726, 1299, 828, 925, 1217, 1254, 963, 1426, 1213, 1394, 2108, 1356, 1448, 1286, 1564, 1455
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OFFSET
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1,1
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COMMENTS
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Sequence is underdefined. The original author may have intended to say that the terms must be distinct and minimal; perhaps he should clarify. - Jonathan Vos Post, Mar 22 2006
See A092944 for additional clarification of definition.
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LINKS
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EXAMPLE
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a(6) = 28 because 15+16+17+18+19+28 = 113 is prime and 15*16*17*18*19*28 + 1 = 39070081 is prime.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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