OFFSET
1,2
COMMENTS
Essentially the first differences of A361512.
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..17905
MATHEMATICA
nn = 750; c[_] = False; f[n_] := DivisorSigma[0, n]; a[1] = k = m = 1; MapAt[# + 1 &, #, 1] &@ Reap[Do[(If[c[#], a[n] = # + f[a[m]] ; m++, a[n] = f[#] ; Sow[n - k - 1]; Set[k, n - 1]]; c[#] = True) &[a[n - 1]], {n, 2, nn}] ][[-1, -1]] (* Michael De Vlieger, Apr 08 2023 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Apr 08 2023
STATUS
approved