Numbers k such that sigma(k) = 2*sigma(k+1).

Terms

a(0) =12a(1) =70a(2) =88a(3) =204a(4) =220a(5) =1750a(6) =1888a(7) =2958a(8) =8142a(9) =8632a(10) =9114a(11) =14664a(12) =18414a(13) =18762a(14) =20118a(15) =20712a(16) =25194a(17) =45520a(18) =64206a(19) =65652a(20) =65964a(21) =77814a(22) =79338a(23) =79824a(24) =85096a(25) =90804a(26) =103410a(27) =103644a(28) =117822a(29) =158946