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A124660
a(n) = Sum_{k=1..n-2} ( prime(n+k)/2 + prime(n-k)/2 - prime(n) ).
1
0, 2, -1, 5, 4, 16, 17, 3, 24, 6, 9, 42, 50, 27, 10, 56, 40, 59, 119, 103, 130, 110, 50, 83, 167, 204, 302, 349, 102, 141, 130, 243, 103, 233, 225, 219, 287, 282, 277, 437, 273, 438, 524, 700, 428, 148, 236, 427, 532, 548, 772, 580, 598, 614, 628, 864, 884, 1018, 1274, 1053
OFFSET
3,2
MAPLE
A124660 := proc(n) add( (ithprime(n+k)+ithprime(n-k))/2-ithprime(n), k=1..n-2) ; end proc:
seq(A124660(n), n=3..80) ; # R. J. Mathar, Mar 28 2010
CROSSREFS
Sequence in context: A309976 A257516 A346800 * A217104 A141485 A005605
KEYWORD
sign,easy
AUTHOR
Artur Jasinski, Dec 23 2006
EXTENSIONS
Offset corrected and sequence extended by R. J. Mathar, Mar 28 2010
STATUS
approved