Numbers k such that sigma(k + sigma(k)) = sigma((k+1) + sigma(k+1)).

Terms

a(0) =4a(1) =7a(2) =16a(3) =50a(4) =494a(5) =4485a(6) =12585a(7) =20606a(8) =45590a(9) =46761a(10) =48614a(11) =64785a(12) =72609a(13) =137853a(14) =169898a(15) =196934a(16) =224186a(17) =321986a(18) =363037a(19) =466545a(20) =474573a(21) =532441a(22) =702374a(23) =811004a(24) =910125a(25) =982310a(26) =1141281a(27) =1282436a(28) =1288557a(29) =1531245