Numbers k such that sigma(k) divides sigma(k+1), where sigma(k) is sum of positive divisors of k.

Terms

a(0) =1a(1) =5a(2) =14a(3) =125a(4) =206a(5) =957a(6) =1253a(7) =1334a(8) =1364a(9) =1634a(10) =1673a(11) =1919a(12) =2685a(13) =2759a(14) =2974a(15) =3127a(16) =4364a(17) =5191a(18) =7615a(19) =11219a(20) =12035a(21) =14841a(22) =18873a(23) =19358a(24) =20145a(25) =24957a(26) =27089a(27) =33998a(28) =36566a(29) =42818