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A097909 Decimal expansion of Sum_{i >= 1} t(i)/g(i), where t(i) = triangular number(i) and g(i) = (sum of first i primes)^4. 0
0, 6, 8, 0, 5, 5, 9, 4, 0, 8, 1, 5, 2, 5, 7, 5, 6, 9, 3, 2, 6, 3, 1, 3, 6, 5, 1, 5, 1, 0, 0, 4, 6, 1, 5, 0, 2, 8, 8, 4, 4, 5, 9, 8, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..44.

FORMULA

Equals Sum_{n>=1} A000217(n)/A007504(n)^4. - R. J. Mathar, Dec 07 2014

EXAMPLE

0.0680559408152575...

MATHEMATICA

p = s = 0; Do[p += Prime[n]; k = n*(n+1)/2; s += k/p^4; Print[N[s, 50]], {n, 10^6}] (* Ryan Propper, Jul 22 2006 *)

CROSSREFS

Cf. A000217, A007504.

Sequence in context: A021151 A200116 A308314 * A143819 A021599 A072553

Adjacent sequences:  A097906 A097907 A097908 * A097910 A097911 A097912

KEYWORD

cons,more,nonn

AUTHOR

Pierre CAMI, Sep 04 2004

EXTENSIONS

Corrected and extended by Ryan Propper, Jul 22 2006

Offset corrected by R. J. Mathar, Jan 31 2009

More terms from Jon E. Schoenfield, Nov 17 2018

STATUS

approved

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Last modified May 22 09:50 EDT 2022. Contains 353949 sequences. (Running on oeis4.)