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A134474 a(n) = numerator of Sum_{k=1..n} 1/A134473(k). 5
1, 3, 32, 5969141, 19747269546873779, 63904014199087613123872206552133781224, 31002867396652810808343087989440323100946378567671674124759425791429267942552085359 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The denominator of Sum_{k=1..n} 1/A134473(k) is A134475(n). A134474(n)/A134475(n) approaches a constant (0.6037789...) as n approaches infinity.

LINKS

Table of n, a(n) for n=1..7.

MAPLE

Digits := 220 ; A134473 := proc(n) option remember ; local su, mu ; if n =1 then 2; else su := add(1/procname(k), k=1..n-1) ; mu := mul(1/(1+1/procname(j)), j=1..n-1) ; ceil( (1+su+sqrt((su-1)^2+4*mu))/2/(mu-su) ) ; fi; end: A134474 := proc(n) add(1/A134473(k), k=1..n) ; numer(%) ; end: seq(A134474(n), n=1..9) ; # R. J. Mathar, Jul 20 2009

CROSSREFS

Cf. A134473, A134475, A134476, A134477.

Sequence in context: A054780 A203323 A222683 * A096469 A106423 A077328

Adjacent sequences:  A134471 A134472 A134473 * A134475 A134476 A134477

KEYWORD

frac,nonn

AUTHOR

Leroy Quet, Oct 27 2007

EXTENSIONS

More terms from R. J. Mathar, Jul 20 2009

STATUS

approved

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Last modified November 26 17:52 EST 2021. Contains 349343 sequences. (Running on oeis4.)