**a(1)=1; for n>1, a(n)=a(n-1)+4 if n is already in the sequence, a(n)=a(n-1)+2 otherwise.**

*1, 3, 7, 9, 11, 13, 17, 19, 23, 25, 29, 31, 35, 37, 39, 41, 45, 47, 51, 53, 55, 57, 61, 63*

*5 seqfan posts*

Index of A-numbers in seqfan: by ascending order by month by frequency by keyword

Links to OEIS content are included according to The OEIS End-User License Agreement .