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A059880 Positions of negative terms in A059876. 2
8, 32, 33, 34, 35, 36, 64, 65, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 152, 160, 161, 256, 257, 258, 259, 260, 261, 262, 263, 264, 265, 266, 267, 268, 269, 270, 272, 273, 274, 275 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..53.

MAPLE

negative_terms(A059876); negative_terms := proc(b) local a, i; a := []; for i from 1 to nops(b) do if(b[i] < 0) then a := [op(a), i]; fi; od; RETURN(a); end;

MATHEMATICA

a[n_] := With[{s = Floor[Log[2, n]]}, (-1)^(n+1) + Sum[(-1)^(Floor[n/2^i] + 1)*Prime[i], {i, 1, s}] + If[1 == n, 1, Mod[s + 1, 2]*Prime[s]]];

A059880 = Position[Array[a, 500], _?Negative] // Flatten (* Jean-Fran├žois Alcover, Mar 07 2016 *)

CROSSREFS

Sequence in context: A299448 A300086 A115948 * A144096 A127988 A129749

Adjacent sequences:  A059877 A059878 A059879 * A059881 A059882 A059883

KEYWORD

nonn

AUTHOR

Antti Karttunen, Feb 05 2001

STATUS

approved

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Last modified November 17 00:02 EST 2018. Contains 317275 sequences. (Running on oeis4.)