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 A283451 a(n) = Sum_{k=1..n} (-1)^k * A005185(k). 1
 -1, 0, -2, 1, -2, 2, -3, 2, -4, 2, -4, 4, -4, 4, -6, 3, -7, 4, -7, 5, -7, 5, -7, 9, -5, 9, -7, 9, -7, 9, -11, 6, -11, 9, -12, 7, -13, 9, -12, 10, -13, 10, -14, 10, -14, 10, -14, 18, -6, 19, -11, 17, -9, 21, -9, 19, -13, 17, -15, 17, -15, 17, -23, 10, -21, 17, -18, 15, -24, 16, -21 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Altug Alkan, Table of n, a(n) for n = 1..10000 Altug Alkan, Alternative Scatterplot of A283451 EXAMPLE a(7) = -3 because -1 + 1 - 2 + 3 - 3 + 4 - 5 = -3. PROG (PARI) a=vector(1000); a[1]=a[2]=1; for(n=3, #a, a[n]=a[n-a[n-1]]+a[n-a[n-2]]); va = vector(#a, n, sum(k=1, n, (-1)^(k)*a[k])) CROSSREFS Cf. A005185, A076268. Sequence in context: A025066 A060426 A260412 * A172245 A238781 A319439 Adjacent sequences:  A283448 A283449 A283450 * A283452 A283453 A283454 KEYWORD sign,look AUTHOR Altug Alkan, Mar 07 2017 STATUS approved

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Last modified May 29 04:33 EDT 2020. Contains 334697 sequences. (Running on oeis4.)