Numbers k such that the odd part of sigma(sigma(k)) is equal to the odd part of sigma(k).

Terms

a(0) =1a(1) =5a(2) =12a(3) =427a(4) =9120a(5) =9180a(6) =9504a(7) =9720a(8) =9960a(9) =10296a(10) =10620a(11) =10740a(12) =10824a(13) =11070a(14) =11310a(15) =11480a(16) =11484a(17) =11556a(18) =11628a(19) =11748a(20) =11934a(21) =11960a(22) =12024a(23) =12036a(24) =12072a(25) =12084a(26) =12376a(27) =12460a(28) =12510a(29) =12570