a(n) is the least integer k such that sigma(k)/(d(k)*sopf(k)) = n where d=A000005, sigma=A000203 and sopf=A008472.

A328174

a(n) is the least integer k such that sigma(k)/(d(k)*sopf(k)) = n where d=A000005, sigma=A000203 and sopf=A008472.

Terms

    a(0) =20a(1) =140a(2) =54a(3) =189a(4) =378a(5) =1365a(6) =540a(7) =945a(8) =1120a(9) =1755a(10) =1539a(11) =3465a(12) =500a(13) =1815a(14) =4256a(15) =6384a(16) =14645a(17) =5280a(18) =1323a(19) =1029a(20) =864a(21) =23871a(22) =34579a(23) =12903a(24) =1715a(25) =2673a(26) =11934a(27) =5589a(28) =106805a(29) =12285

External references