Index of first occurrence of n in A120125, or 0 if not present.

Terms

a(0) =0a(1) =1a(2) =2a(3) =3a(4) =4a(5) =5a(6) =6a(7) =7a(8) =8a(9) =9a(10) =10a(11) =5654a(12) =15a(13) =20a(14) =35a(15) =45a(16) =50a(17) =55a(18) =39a(19) =29a(20) =21a(21) =64a(22) =5064a(23) =11a(24) =25a(25) =30a(26) =40a(27) =46a(28) =56a(29) =34