a(n) is the index of the smallest square pyramidal number with exactly n prime factors (counted with multiplicity).

A359193

a(n) is the index of the smallest square pyramidal number with exactly n prime factors (counted with multiplicity).

Terms

    a(0) =1a(1) =2a(2) =3a(3) =4a(4) =7a(5) =15a(6) =24a(7) =31a(8) =63a(9) =80a(10) =175a(11) =255a(12) =511a(13) =1023a(14) =512a(15) =6912a(16) =2047a(17) =6655a(18) =14336a(19) =16384a(20) =32767a(21) =90112a(22) =131071a(23) =180224a(24) =483327a(25) =1114112a(26) =1638400a(27) =2097151a(28) =1048575a(29) =16777216

External references