A205098 Sum of proper divisors (A001065) of abundant numbers (A005101).

16, 21, 22, 36, 42, 55, 50, 54, 76, 66, 64, 108, 78, 74, 123, 90, 106, 140, 92, 144, 156, 117, 114, 106, 172, 136, 126, 240, 186, 204, 150, 196, 259, 222, 236, 218, 201, 312, 186, 196, 366, 198, 316, 203, 270, 265, 300, 226, 366, 384, 284, 234, 280, 332, 312

Offset: 1

Author

Jaroslav Krizek, Jan 22 2012

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000
• Eric Weisstein's World of Mathematics, Abundant Number.
• Eric Weisstein's World of Mathematics, Restricted Divisor Function.

Crossrefs

Cf. A205099 (sum of proper divisors of deficient numbers), A204822 (sum of divisors of abundant numbers), A001065, A005101.

Programs

Mathematica

f[n_] := Module[{s = DivisorSigma[1, n] - n}, If[s > n, s, Nothing]]; Array[f, 250] (* Amiram Eldar, Mar 11 2024 *)

Formula

a(n) = A001065(A005101(n)) = A204822(n) - A005101(n).