Numbers n such that 2n-1 and 2n+1 divide 2^n-1.

Terms

a(0) =8a(1) =128a(2) =228a(3) =648a(4) =3240a(5) =5976a(6) =13160a(7) =23760a(8) =23940a(9) =24840a(10) =32768a(11) =37224a(12) =78540a(13) =82800a(14) =139248a(15) =166716a(16) =238368a(17) =278520a(18) =280368a(19) =288360a(20) =516528a(21) =633420a(22) =664668a(23) =731808a(24) =734448a(25) =1145520a(26) =1211100a(27) =1377240a(28) =1425816a(29) =1484568