A396624 a(n) = r(n,n), where r(1,k)=f(k)=round(k*c), r(n,k)=f(r(n-1,k)), c=sqrt(3).

2, 5, 16, 36, 83, 151, 320, 655, 1294, 2357, 4619, 8639, 16844, 30616, 56790, 104812, 190901, 355762, 647964, 1209236, 2099298, 3880726, 7089589, 12885826, 22740746, 41399828, 74229365, 132342905, 241044147, 431161540, 778051684, 1365541232, 2454485501

Offset

1,1

Comments

a(n + 1)/a(n) approaches c erratically.

Links

Table of n, a(n) for n=1..33.

Mathematica

c = Sqrt[3]; f[k_] := f[k] = Round[c*k];
r[1, k_] := f[k]; r[n_, k_] := r[n, k] = f[r[n - 1, k]];
Table[r[n, n], {n, 1, 100}]

Crossrefs

Cf. A396385, A396622, A396624.

Sequence in context: A174988 A364706 A053683 * A305876 A082085 A179992

Adjacent sequences: A396621 A396622 A396623 * A396625 A396626 A396627

Keyword

nonn

Author

Clark Kimberling, Jun 04 2026

Status

approved