Numbers n such that n*phi(n-1) is a perfect square.

Terms

a(0) =9a(1) =27a(2) =45a(3) =49a(4) =64a(5) =486a(6) =637a(7) =867a(8) =961a(9) =1035a(10) =1352a(11) =1408a(12) =1521a(13) =3971a(14) =4913a(15) =7581a(16) =8750a(17) =12936a(18) =14283a(19) =19602a(20) =20825a(21) =23104a(22) =36481a(23) =43681a(24) =44506a(25) =48600a(26) =49005a(27) =58621a(28) =63001a(29) =72897