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A033468 Partial sums of sequence {1/(i^2+1): i=0..n} (denominators). 3
1, 2, 10, 5, 85, 2210, 81770, 204425, 204425, 16762850, 1693047850, 51637959425, 1497500823325, 2995001646650, 590015324390050, 33335865828037825, 8567317517805721025, 17134635035611442050 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Robert Israel, Table of n, a(n) for n = 0..389

MAPLE

S:= 0:

for i from 0 to 50 do

  S:= S + 1/(i^2+1);

  A[i]:= denom(S)

od:

seq(A[i], i=0..50); # Robert Israel, Apr 27 2020

MATHEMATICA

Accumulate[Table[1/(n^2+1), {n, 0, 20}]]//Denominator (* Harvey P. Dale, Jan 20 2020 *)

PROG

(PARI) for(n=0, 20, print1(denominator(sum(k=0, n, 1/(k^2+1))), ", ")) \\ Hugo Pfoertner, Apr 27 2020

CROSSREFS

Cf. A033467.

Sequence in context: A070730 A082192 A276850 * A047816 A095845 A105801

Adjacent sequences:  A033465 A033466 A033467 * A033469 A033470 A033471

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified January 22 06:03 EST 2021. Contains 340360 sequences. (Running on oeis4.)