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A105174
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Numbers n such that n*(n+1)/4 - 1 and n*(n+1)/4 + 1 are twin primes.
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2
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8, 15, 23, 24, 71, 80, 104, 128, 159, 216, 231, 264, 288, 303, 336, 344, 455, 495, 528, 543, 560, 608, 624, 680, 744, 816, 840, 879, 896, 1016, 1104, 1311, 1415, 1440, 1464, 1520, 1584, 1599, 1751, 1871, 1896, 1920, 1976, 2015, 2016, 2055, 2088, 2103, 2175
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| The twin primes are = (sum of numbers from 1 to n)/2 -1 and +1
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EXAMPLE
| 8*9/4=18, 17 and 19 twin primes so a(1)=8
15*16/4=60, 59 and 61 twin primes so a(2)=15
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CROSSREFS
| Sequence in context: A079043 A024734 A024956 * A126622 A109332 A167986
Adjacent sequences: A105171 A105172 A105173 * A105175 A105176 A105177
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KEYWORD
| nonn
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AUTHOR
| Pierre CAMI (pierre-cami(AT)bbox.fr), Apr 11 2005
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EXTENSIONS
| More terms from Zak Seidov (zakseidov(AT)yahoo.com), Oct 07 2009
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