a(n) = n * Sum_{d|n} binomial(n,d)/gcd(n,d).

Terms

a(0) =1a(1) =5a(2) =10a(3) =29a(4) =26a(5) =122a(6) =50a(7) =317a(8) =334a(9) =830a(10) =122a(11) =4754a(12) =170a(13) =7698a(14) =11510a(15) =34237a(16) =290a(17) =159530a(18) =362a(19) =458054a(20) =358592a(21) =1413890a(22) =530a(23) =8236946a(24) =266276a(25) =20806102a(26) =14087530a(27) =85118762a(28) =842a(29) =404242022