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A074800 a(1)=1; for n>1, a(n) is the denominator of b(n) = (4*n+1)*(prod(i=1,n,2*i-1)/prod(i=1,n,2*i))^5. 1
1, 32, 32768, 1048576, 34359738368, 1099511627776, 1125899906842624, 36028797018963968, 37778931862957161709568, 1208925819614629174706176, 1237940039285380274899124224, 39614081257132168796771975168 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

REFERENCES

Bruce C. Berndt and Robert Rankin,"Ramanujan: letters and commentary", AMS-LMS, History of Mathematics, vol. 9, p. 57

FORMULA

1+sum(k>=1, (-1)^k*b(k))=2/gamma(3/4)^4=0.88694116857811540541...

PROG

(PARI) a(n)=denominator ((4*n+1)*(prod(i=1, n, 2*i-1)/prod(i=1, n, 2*i))^5)

CROSSREFS

Cf. A074799.

Sequence in context: A016877 A123393 A016937 * A159396 A054374 A017009

Adjacent sequences:  A074797 A074798 A074799 * A074801 A074802 A074803

KEYWORD

easy,frac,nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Sep 08 2002

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Last modified February 17 03:18 EST 2012. Contains 205978 sequences.