Position of n-th 0 in A031253.

Terms

a(0) =4a(1) =14a(2) =24a(3) =25a(4) =27a(5) =30a(6) =40a(7) =55a(8) =63a(9) =66a(10) =70a(11) =85a(12) =99a(13) =100a(14) =102a(15) =105a(16) =115a(17) =130a(18) =138a(19) =141a(20) =145a(21) =160a(22) =174a(23) =175a(24) =176a(25) =178a(26) =179a(27) =182a(28) =183a(29) =186