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A062021
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Let P(n) = { 2,3,5,7,...,p(n) } where p(n) is n-th prime; then a(1) =0 and a(n) = Sum [mod{p(i)^2 - p(j)^2}], for all i and j from 1 to n.
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0
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0, 5, 42, 151, 548, 1185, 2542, 4403, 7608, 13621, 20834, 32535, 47980, 65609, 88278, 119947, 162368, 208869, 269194, 340007, 416580, 512305, 622286, 756003, 925432, 1114661, 1314498, 1537015, 1771628, 2031993, 2393158, 2786315
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| a(n) = 2*a(n-1) + (n-1)*(p(n)^2-p(n-1)^2) - a(n-2)
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EXAMPLE
| a(3) = (5^2-2^2) + (5^2-3^2) + (3^2-2^2) = 42, P(3) = {2,3,5}.
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CROSSREFS
| Sequence in context: A065035 A145008 A025173 * A082145 A126765 A024492
Adjacent sequences: A062018 A062019 A062020 * A062022 A062023 A062024
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KEYWORD
| nonn
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Jun 02 2001
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EXTENSIONS
| More terms and formula from Larry Reeves (larryr(AT)acm.org), Jun 06 2001
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