Basis for code in A075946.

Terms

a(0) =1023a(1) =31775a(2) =232551a(3) =824491a(4) =1386837a(5) =6330581a(6) =25206065a(7) =42278310a(8) =77607100a(9) =402698573a(10) =673253467a(11) =1218520349a(12) =6442523019a(13) =10748180761a(14) =51539687634a(15) =86033873250a(16) =156768744521a(17) =824634027372