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 A369508 Decimal expansion of Sum_{n>=1} prime(n)*(-1/2)^n (negated). 0
 6, 6, 2, 7, 2, 9, 7, 8, 4, 1, 8, 5, 2, 6, 7, 9, 6, 5, 3, 8, 8, 3, 3, 7, 6, 9, 4, 4, 6, 3, 9, 9, 8, 0, 5, 4, 7, 2, 2, 3, 6, 9, 6, 0, 8, 7, 9, 9, 6, 4, 0, 0, 4, 0, 9, 6, 7, 7, 8, 5, 6, 9, 1, 0, 2, 1, 8, 3, 0, 6, 1, 1, 9, 9, 4, 2, 0, 8, 2, 6, 6, 8, 8, 1, 5 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS Table of n, a(n) for n=0..84. EXAMPLE 0.662729784185267965388337694463998... MATHEMATICA First[RealDigits[Sum[Prime[n](-2)^-n, {n, 1000}], 10, 85]] (* James C. McMahon, Jan 29 2024 *) PROG (Python) from sympy import prime from decimal import Decimal, getcontext getcontext().prec = 100 def f(k): if k == 1: return prime(k) * Decimal(-0.5) return f(k-1) + prime(k) * Decimal(-0.5) ** k (PARI) suminf(k=1, prime(k)/(-2)^k) \\ Michel Marcus, Jan 25 2024 CROSSREFS Cf. A098990. Sequence in context: A218387 A178857 A003676 * A033259 A212298 A064926 Adjacent sequences: A369505 A369506 A369507 * A369509 A369510 A369511 KEYWORD nonn,cons AUTHOR Pierluigi Failla, Jan 25 2024 STATUS approved

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Last modified July 13 08:08 EDT 2024. Contains 374274 sequences. (Running on oeis4.)