Numbers k that divide s(k), where s(1)=1, s(j)=5*s(j-1)+j.

Terms

a(0) =1a(1) =5a(2) =55a(3) =355a(4) =605a(5) =3905a(6) =6655a(7) =25205a(8) =42955a(9) =73205a(10) =201995a(11) =277255a(12) =472505a(13) =805255a(14) =1789555a(15) =2221945a(16) =3049805a(17) =5197555a(18) =5693105a(19) =6049555a(20) =7321105a(21) =8857805a(22) =14341645a(23) =19685105a(24) =24441395a(25) =28150705a(26) =33547855a(27) =57173105a(28) =62624155a(29) =66545105