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A119248 Difference between denominator and numerator of the n-th alternating harmonic number Sum[(-1)^(k+1)*1/k,{k,1,n}] = A058313(n)/A058312(n). 0
0, 1, 1, 5, 13, 23, 101, 307, 641, 893, 7303, 9613, 97249, 122989, 19793, 48595, 681971, 818107, 13093585, 77107553, 66022193, 76603673, 1529091919, 1752184789, 7690078169, 8719737569, 23184641107, 3721854001, 96460418429 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..29.

FORMULA

a(n) = Denominator[Sum[(-1)^(k+1)*1/k,{k,1,n}]] - Numerator[Sum[(-1)^(k+1)*1/k,{k,1,n}]]. a(n) = A058312(n) - A058313(n). a(n) = A075829(n+1).

MATHEMATICA

Denominator[Table[Sum[(-1)^(k+1)*1/k, {k, 1, n}], {n, 1, 30}]]-Numerator[Table[Sum[(-1)^(k+1)*1/k, {k, 1, n}], {n, 1, 30}]]

CROSSREFS

Cf. A058312, A058313, A075829.

Sequence in context: A049833 A083800 A075829 * A114998 A140090 A271937

Adjacent sequences:  A119245 A119246 A119247 * A119249 A119250 A119251

KEYWORD

nonn

AUTHOR

Alexander Adamchuk, Jul 22 2006

STATUS

approved

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Last modified April 24 04:00 EDT 2019. Contains 322406 sequences. (Running on oeis4.)