A073594 Numerator of b(n) = Sum_{k=1..n} (-1)^(k+1)/k*Sum_{i=0..k-1} (-1)^i/(2*i+1).

1, 2, 43, 244, 1483, 42494, 4421639, 3975704, 17273323, 3917984134, 46801334969, 1002549557332, 735057842971, 13139661722338, 2022120072706607, 59425819929320912, 1064450614009503859, 3045237174301650742, 2242901701823948775361, 2149021201829850641044

Offset

1,2

Links

Amiram Eldar, Table of n, a(n) for n = 1..772

Formula

Limit_{n -> infinity} b(n) = G, the Catalan constant (A006752).

Mathematica

Numerator[Accumulate[Table[(-1)^(k + 1)/k * Sum[(-1)^i/(2*i + 1), {i, 0, k - 1}], {k, 1, 20}]]] (* Amiram Eldar, May 05 2022 *)

Prog

(PARI) a(n)=numerator( sum(k=1, n, (-1)^(k+1)/k*sum(i=0, k-1, (-1)^i/(2*i+1))))

Crossrefs

Cf. A006752, A073595 (denominators).

Sequence in context: A079823 A107156 A062582 * A349927 A112097 A354304

Adjacent sequences: A073591 A073592 A073593 * A073595 A073596 A073597

Keyword

easy,frac,nonn

Author

Benoit Cloitre, Aug 28 2002

Status

approved