Numbers n such that sigma(n) = sigma(n+1) - sigma(n-1).

Terms

a(0) =2a(1) =3a(2) =23a(3) =1967a(4) =3263a(5) =5015a(6) =60455a(7) =1016507a(8) =4420163a(9) =12055511a(10) =14365607a(11) =25726727a(12) =27896423a(13) =66562307a(14) =72764735a(15) =98734967a(16) =175186655a(17) =224868311a(18) =253694927a(19) =288657203a(20) =386668343a(21) =421575407a(22) =504737747a(23) =630645455a(24) =1493547999