A353616 a(n) is the denominator of the median abundancy index of the first 2^n + 1 positive integers.

3, 3, 9, 2, 21, 29, 41, 59, 73, 107, 139, 157, 4941, 7707, 157, 1929, 1973, 7643, 147749, 313733, 1774479, 1015973, 1615943, 6646647, 3280781, 5670497, 31673271, 21228137

Offset: 1

Author

Amiram Eldar, Apr 30 2022

Keywords

• nonn
• frac
• more

Comments

See A353615 for more details.

Crossrefs

Cf. A000203, A017665, A017666, A353615 (numerators), A353617.

Programs

Mathematica

With[{m = 20}, t = Table[DivisorSigma[-1, n], {n, 1, 2^m + 1}]; Denominator @ Table[Median[t[[1 ;; 2^n + 1]]], {n, 1, m}]]