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 A151960 Sum_{x = A141468(n) to A000040(n)} 1-(-1)^x*x. 0
 2, 5, 3, 3, 6, 16, 12, 12, 15, 37, 24, 30, 33, 55, 39, 45, 77, 54, 88, 66, 66, 72, 109, 84, 129, 99, 99, 142, 105, 108, 126, 175, 138, 138, 200, 153, 211, 168, 171, 233, 186, 244, 201, 201, 204, 268, 222, 303, 243, 243, 316, 255, 255, 267, 349, 282 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE a(1)=1-0+1+1+1-2=2, a(2)=1+1+1-2+1+3=5, a(3)=1-4+1+5=3, a(4)=1-6+1+7=3, a(5)=1-8+1+9+1-10+1+11=6, a(6)=1+9+1-10+1+11+1-12+1+13=16, a(7)=1-10+1+11+1-12+1+13+1-14+1+15+1-16+1+17=12, a(8)=1-12+1+13+1-14+1+15+1-16+1+17+1-18+1+19=12, a(9)=1-14+1+15+1-16+1+17+1-18+1+19+1-20+1+21+1-22+1+23=15, a(10)=1+15+1-16+1+17+1-18+1+19+1-20+1+21+1-22+1+23+1-24+1+25+1-26+1+27+1-28+1+29=37, ... MATHEMATICA ZeroAndNonPrime[n_Integer] := FixedPoint[n - 1 + PrimePi@# &, n - 1 + PrimePi@n]; ZeroAndNonPrime[2] = 1; f[n_] := Sum[1-(-1)^x*x, {x, ZeroAndNonPrime@n, Prime@n}]; Array[f, 56] CROSSREFS Cf. A000040, A141468, A161669. Sequence in context: A162405 A141637 A185581 * A281300 A115320 A073480 Adjacent sequences:  A151957 A151958 A151959 * A151961 A151962 A151963 KEYWORD nonn AUTHOR Juri-Stepan Gerasimov, Jul 14 2009 EXTENSIONS Edited, corrected and extended by Robert G. Wilson v, Jul 24 2009 Definition clarified by N. J. A. Sloane, Jul 25 2009 Definition corrected by Charles R Greathouse IV, Jul 22 2010 STATUS approved

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Last modified April 17 15:33 EDT 2021. Contains 343063 sequences. (Running on oeis4.)