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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
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
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.)