A363692 Terms of A363690 with a record number of divisors.
3, 6, 12, 24, 36, 48, 72, 144, 168, 288, 336, 420, 840, 1680, 3360, 6720, 7560, 15120, 30240, 60480, 95760, 120960, 176400, 191520, 257040, 352800, 383040, 514080, 1028160, 1681680, 2056320, 2998800, 3112200, 5525520, 5997600, 6224400, 8353800, 12448800, 16216200
Offset: 1
Links
- David A. Corneth, Table of n, a(n) for n = 1..160 (first 56 terms from Amiram Eldar)
Programs
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Mathematica
seq[kmax_] := Module[{s = {}, dm = 0, d1}, Do[d1 = DivisorSigma[0, k]; If[d1 > dm && DivisorSum[k, Boole[BitOr[#, k] == k] &] == 2, dm = d1; AppendTo[s, k]], {k, 1, kmax}]; s]; seq[10^5] -
PARI
lista(kmax) = {my(dm = 0, d1); for(k = 1, kmax, d1 = numdiv(k); if(d1 > dm && sumdiv(k, d, bitor(d, k) == k) == 2, dm = d1; print1(k, ", "))); }
Formula
a(n) <= 2*a(n-1) for n >= 2. - David A. Corneth, Jun 18 2023
Comments