Numbers k such that sigma(k - 2) = sigma(k + 2).

Terms

a(0) =53a(1) =68a(2) =117a(3) =222a(4) =321a(5) =1005a(6) =2587a(7) =4026a(8) =4185a(9) =4197a(10) =5722a(11) =5828a(12) =5961a(13) =8006a(14) =8376a(15) =11661a(16) =12369a(17) =12563a(18) =13583a(19) =14340a(20) =15367a(21) =16118a(22) =17842a(23) =18720a(24) =20543a(25) =25132a(26) =29395a(27) =30172a(28) =32667a(29) =36518