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

A025546

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

Terms

    a(0) =1a(1) =1a(2) =5a(3) =7a(4) =71a(5) =41a(6) =467a(7) =299a(8) =913a(9) =633a(10) =885a(11) =645a(12) =9615a(13) =7305a(14) =47613a(15) =480369a(16) =1841507a(17) =1455407a(18) =1815767a(19) =2955859a(20) =3611059a(21) =50577203a(22) =61079123a(23) =50868923a(24) =1150293137a(25) =971221937a(26) =1145816357a(27) =979535957a(28) =1138258157a(29) =983063117

External references