A138671 Indices of 1's in Stewart's choral sequence.
2, 5, 7, 8, 11, 14, 16, 17, 20, 22, 23, 25, 26, 29, 32, 34, 35, 38, 41, 43, 44, 47, 49, 50, 52, 53, 56, 59, 61, 62, 65, 67, 68, 70, 71, 74, 76, 77, 79, 80, 83, 86, 88, 89, 92, 95, 97, 98, 101, 103, 104
Offset: 0
Formula
3^{m+1}n+(5(3^m)-1)/2 for m,n in {0,1,2,...}