Triangular numbers in which the k-th significant digit either divides k or is a multiple of k.

Terms

a(0) =1a(1) =3a(2) =6a(3) =15a(4) =21a(5) =28a(6) =45a(7) =66a(8) =325a(9) =666a(10) =946a(11) =1128a(12) =1326a(13) =2145a(14) =2346a(15) =2628a(16) =2926a(17) =4186a(18) =8128a(19) =8385a(20) =8646a(21) =8911a(22) =11325a(23) =11628a(24) =14365a(25) =18145a(26) =18915a(27) =51681a(28) =52326a(29) =54615