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Numbers m such that A076644(m) = floor((2/3)*m*(sqrt(m)+1)).
2

%I #18 Feb 16 2021 10:50:04

%S 1,2,6,17,24,26,29,43,83,88,193,207,243,357,534,806,1082,1197,1377,

%T 2246,2362,3148,4342,4570,6463,11687,14305,35681,41369,53410,75292,

%U 98348,146608,219393,246121,257663,419767,476246,596919,860060,912227,1225215,2239828,2727103,2819396

%N Numbers m such that A076644(m) = floor((2/3)*m*(sqrt(m)+1)).

%C Sequence is probably infinite.

%H Michel Marcus, <a href="/A076660/b076660.txt">Table of n, a(n) for n = 1..50</a>

%F It seems that a(n) is asymptotic to c*exp(d*n) with d around 0.33...

%o (PARI) lista(nn) = {my(v=vector(nn)); v[1] = 1; for (n=2, nn, v[n] = n + v[n-sqrtint(n)]; ); for (m=1, nn, if (v[m] == floor((2/3)*m*(sqrt(m)+1)), print1(m, ", ")););} \\ _Michel Marcus_, Feb 16 2021

%Y Cf. A076644.

%K nonn

%O 1,2

%A _Benoit Cloitre_, Oct 24 2002

%E Incorrect term 4 removed and more terms added from _Michel Marcus_, Feb 16 2021