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Search: id:A062046
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| A062046 |
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Sum of even numbers between consecutive primes. |
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+0
2
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| 0, 4, 6, 18, 12, 30, 18, 42, 78, 30, 102, 78, 42, 90, 150, 168, 60, 192, 138, 72, 228, 162, 258, 372, 198, 102, 210, 108, 222, 840, 258, 402, 138, 720, 150, 462, 480, 330, 510, 528, 180, 930, 192, 390, 198, 1230, 1302, 450, 228, 462, 708, 240, 1230, 762, 780
(list; graph; listen)
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OFFSET
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1,2
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LINKS
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Harry J. Smith, Table of n, a(n) for n=1,...,1000
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FORMULA
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a(n) = {p(n+1) +p(n)}*{p(n+1) - p(n)}/4 = {p(n+1)^2 - p(n)^2}/4
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EXAMPLE
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a(4) = 18 = 8+10 as the even numbers between 7 and 11 are 8 and 10. a(4) = (11+7)(11-7)/4 = 18.
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PROGRAM
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(PARI) { for (n=1, 1000, a=(prime(n + 1)^2 - prime(n)^2)/4; if (n==1, a=0); write("b062046.txt", n, " ", a) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Jul 30 2009]
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CROSSREFS
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a(n)= ( p(n) + e(n)) * e(n), e(n) := A001223(n) / 2, for n > 1
Sequence in context: A079803 A061361 A113610 this_sequence A102020 A125133 A109310
Adjacent sequences: A062043 A062044 A062045 this_sequence A062047 A062048 A062049
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KEYWORD
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nonn
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AUTHOR
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Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Jun 06 2001
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EXTENSIONS
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More terms from Larry Reeves (larryr(AT)acm.org), Jun 07 2001
OFFSET changed from 0,2 to 1,2 by Harry J. Smith (hjsmithh(AT)sbcglobal.net), Jul 30 2009
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