A339679 Larger of amicable pair (a, b) such that the sum of their number of divisors d(a) + d(b) sets a new record.

284, 1210, 6368, 10856, 14595, 71145, 87633, 525915, 1438983, 1870245, 5120595, 6088905, 11791935, 14084763, 36939357, 207429525, 234587199, 662939925, 1337154465, 2450161791, 4024393191, 4785272037, 10162493523, 38437212933, 160412122575, 229777289469, 248806975131

Offset: 1

Author

Amiram Eldar, Dec 12 2020

Keywords

• nonn

Comments

The terms are ordered according to their lesser counterparts (A339678).

The terms were calculated using data from Chernykh's site.

Links

• Amiram Eldar, Table of n, a(n) for n = 1..55
• Sergei Chernykh, Amicable pairs list.

Crossrefs

Cf. A000005, A002025, A002046, A063990, A328043, A339678.

Programs

Mathematica

s[n_] := DivisorSigma[1, n] - n; dm = 0; seq = {}; Do[m = s[n]; If[m > n && s[m] == n && (d = Plus @@ DivisorSigma[0,{n, m}]) > dm, dm = d; AppendTo[seq, m]], {n,1 ,10^6}]; seq