Squarefree numbers k such that the sum of 1/(p-1) over the prime divisors p of k is 1.

A381507

Squarefree numbers k such that the sum of 1/(p-1) over the prime divisors p of k is 1.

Terms

    a(0) =2a(1) =1365a(2) =73815a(3) =6702045a(4) =8788065a(5) =26241285a(6) =32426205a(7) =237539445a(8) =269409855a(9) =445317015a(10) =475231515a(11) =709296105a(12) =1085962395a(13) =1329722835a(14) =1447857915a(15) =2403281595a(16) =3255993615a(17) =5145721455a(18) =5254163355a(19) =5824953435a(20) =6560751435a(21) =7176232455a(22) =7703697855a(23) =8332635255a(24) =8542035645

External references