A025546 (1/4 - 1/6 + ... + d/c(n))*LCM{4, 6, ..., c(n)}, where d = (-1)^(n-1), c(n) = n-th composite number.

1, 1, 5, 7, 71, 41, 467, 299, 913, 633, 885, 645, 9615, 7305, 47613, 480369, 1841507, 1455407, 1815767, 2955859, 3611059, 50577203, 61079123, 50868923, 1150293137, 971221937, 1145816357, 979535957, 1138258157, 983063117, 26102340091

Offset

1,3

Links

Table of n, a(n) for n=1..31.

Crossrefs

Sequence in context: A130189 A180755 A073624 * A308397 A308848 A109715

Adjacent sequences: A025543 A025544 A025545 * A025547 A025548 A025549

Keyword

nonn

Author

Clark Kimberling

Status

approved