Number of length n 1..(1+1) arrays with every leading partial sum divisible by 2, 3 or 5.

Terms

a(0) =1a(1) =2a(2) =4a(3) =5a(4) =6a(5) =9a(6) =10a(7) =11a(8) =15a(9) =19a(10) =21a(11) =26a(12) =35a(13) =48a(14) =75a(15) =120a(16) =166a(17) =203a(18) =262a(19) =395a(20) =613a(21) =879a(22) =1174a(23) =1502a(24) =1849a(25) =2237a(26) =2738a(27) =3364a(28) =4104a(29) =5107