Numbers n such that phi(4n+1) = sigma(n).

Terms

a(0) =56a(1) =476a(2) =2840a(3) =4676a(4) =8120a(5) =9416a(6) =16256a(7) =23940a(8) =25056a(9) =28520a(10) =30566a(11) =32760a(12) =36146a(13) =37716a(14) =39816a(15) =55676a(16) =56306a(17) =65280a(18) =66056a(19) =129260a(20) =135840a(21) =143096a(22) =149960a(23) =155876a(24) =176736a(25) =185240a(26) =198240a(27) =198396a(28) =202676a(29) =232596