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A120352
Numerator of Sum[ 1/k^p, {k,1,p-1} ], where p = Prime[n].
1
1, 9, 257875, 940908897061, 26038773205374138944970092886340352227, 5706439637514064062030256049808675747470805004854626598761, 3819751175863358416058062379293843331497647520922258560223903226691067255782388923965399403291707829
OFFSET
1,2
COMMENTS
p^3 divides a(n) for n>2. A119722[n] = a(n)/p^3, p=Prime[n].
Numerators of Sum[ 1/k^n, {k,1,n-1} ] are listed in A120347(n) = {1, 9, 1393, 257875, 47463376609, 940908897061, ...}.
FORMULA
a(n) = Numerator[ Sum[ 1/k^Prime[n], {k,1,Prime[n]-1} ]]. a(n) = Numerator[ Zeta[p] - Zeta[p,p] ], for p = Prime[n].
a(n) = A120347[ Prime[n] ].
MATHEMATICA
Table[Numerator[Sum[1/k^Prime[n], {k, 1, Prime[n]-1}]], {n, 1, 8}]
CROSSREFS
Cf. A119722.
Cf. A120347.
Sequence in context: A300195 A368068 A159344 * A225069 A058468 A133414
KEYWORD
frac,nonn
AUTHOR
Alexander Adamchuk, Aug 16 2006, Oct 31 2006
STATUS
approved