%I #9 Apr 09 2023 02:01:10
%S 1,2,2,2,2,3,2,4,3,4,3,4,7,3,5,6,6,8,4,6,3,8,6,6,6,9,5,8,6,8,5,7,7,9,
%T 8,9,9,9,12,9,10,10,10,10,14,7,15,11,14,7,14,11,15,9,11,12,10,15,10,
%U 14,16,10,14,11,13,13,15,13,14,15,19,14,13,17,18,12,13,14,13,16
%N Lengths of rows when A361511 is regarded as an irregular triangle.
%C Essentially the first differences of A361512.
%H Michael De Vlieger, <a href="/A361514/b361514.txt">Table of n, a(n) for n = 1..17905</a>
%t 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 *)
%Y Cf. A361511A361513.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Apr 08 2023
