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A069052 a(n) = denominator of sum_{i=1..n} 1/i^5. 7
1, 32, 7776, 248832, 777600000, 259200000, 4356374400000, 139403980800000, 101625502003200000, 101625502003200000, 16366888723117363200000, 16366888723117363200000, 6076911214672415134617600000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..13.

FORMULA

If 1<=n<=19, a(n) = A007480(n)*A002805(n) = denominator(sum_{i=1..n} 1/i^4)*denominator(sum_{i=1..n} 1/i).

MATHEMATICA

s=0; lst={}; Do[s+=1/n^5; AppendTo[lst, Denominator[s]], {n, 3*4!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jan 24 2009 *)

CROSSREFS

Numerators are A099828.

Sequence in context: A224107 A016829 A248720 * A221614 A086752 A248001

Adjacent sequences:  A069049 A069050 A069051 * A069053 A069054 A069055

KEYWORD

easy,frac,nonn

AUTHOR

Benoit Cloitre, Apr 03 2002

STATUS

approved

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Last modified February 26 10:42 EST 2020. Contains 332279 sequences. (Running on oeis4.)