The triangle in A151338 read by rows upwards.

Terms

a(0) =1a(1) =1a(2) =0a(3) =1a(4) =1a(5) =0a(6) =1a(7) =3a(8) =1a(9) =0a(10) =1a(11) =6a(12) =7a(13) =1a(14) =0a(15) =1a(16) =10a(17) =25a(18) =15a(19) =1a(20) =0a(21) =1a(22) =15a(23) =65a(24) =90a(25) =31a(26) =0a(27) =0a(28) =1a(29) =21