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A157290 Decimal expansion of 105/Pi^4. 4
1, 0, 7, 7, 9, 2, 8, 1, 3, 6, 7, 4, 1, 8, 5, 5, 1, 9, 4, 8, 6, 1, 0, 4, 2, 2, 4, 3, 0, 4, 7, 4, 6, 2, 8, 8, 4, 8, 9, 1, 9, 1, 9, 1, 9, 4, 6, 3, 2, 0, 1, 7, 5, 8, 5, 4, 0, 7, 6, 4, 3, 7, 2, 4, 5, 5, 7, 2, 3, 4, 5, 8, 0, 9, 3, 2, 9, 5, 1, 6, 2, 6, 1, 5, 2, 6, 0, 0, 1, 0, 2, 6, 0, 0, 5, 5, 0, 1, 5, 0, 9, 0, 8, 4, 8 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

The Product_{p = primes = A000040} (1+1/p^4), the quartic analog to A082020.

LINKS

Table of n, a(n) for n=1..105.

FORMULA

Equals A013662/A013666 = Product_{i>=1} (1+1/A030514(i)).

Equals Sum_{k>=1} 1/A005117(k)^4 = 1 + Sum_{k>=1} 1/A113849(k). - Amiram Eldar, May 22 2020

EXAMPLE

1.077928136741855194... = (1+1/2^4)*(1+1/3^4)*(1+1/5^4)*(1+1/7^4)*...

MAPLE

evalf(105/Pi^4) ;

MATHEMATICA

RealDigits[105/\[Pi]^4, 10, 150][[1]]  (* Harvey P. Dale, Mar 20 2011 *)

CROSSREFS

Cf. A005117, A013662, A013666, A030514, A082020, A113849.

Sequence in context: A187179 A110941 A182470 * A021566 A335847 A244649

Adjacent sequences:  A157287 A157288 A157289 * A157291 A157292 A157293

KEYWORD

cons,easy,nonn

AUTHOR

R. J. Mathar, Feb 26 2009

STATUS

approved

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Last modified December 2 02:12 EST 2021. Contains 349435 sequences. (Running on oeis4.)