cp's OEIS Frontend

A365342 Positions of records in A087704.

%I A365342 #26 Sep 15 2023 01:54:14
%S A365342 2,5,10,82,284,680,1322,68104,149795,213895,1023127,3775307,25396927,
%T A365342 36254395,53343289,68677522,266888359,366901277,558829814,1576699732,
%U A365342 8527370677,11616255230,16948492520,167299409017,222801579737,2001199132825,5024272986979,7880897129684
%N A365342 Positions of records in A087704.
%C A365342 Numbers k such that iteration of the map x -> (5/3)*floor(x) starting at x = k takes more steps to reach an integer > k than it does for any number from 2 to k - 1.
%F A365342 A087704(a(n)) = A365343(n).
%e A365342 a(3) = 10 is a term because A087704(10) = 9 and A087704(k) < 9 for 2 <= k < 10.
%p A365342 g:= x -> 5/3 * floor(x):
%p A365342 h:= proc(n) local i,k;
%p A365342   k:= g(n);
%p A365342   for i from 1 while not (k::integer and k > n) do k:= g(k) od:
%p A365342   i
%p A365342 end proc:
%p A365342 M:= 2: A:= 2: count:= 1:
%p A365342 for n from 3 while count < 17  do
%p A365342   v:= h(n);
%p A365342   if v > M then count:= count+1; A:= A,n; M:= v fi;
%p A365342 od:
%p A365342 A;
%t A365342 g =  5/3 * Floor[#]&;
%t A365342 h[n_] := Module[{i, k}, k = g[n]; For[i = 1, !IntegerQ[k] && k > n, i++,  k = g[k]]; i];
%t A365342 M = 2; A = {2}; count = 1;
%t A365342 For[n = 3, count < 17, n++, v = h[n]; If[v > M, count++; A = Append[A, n]; Print[A]; M = v]];
%t A365342 A (* _Jean-François Alcover_, Sep 14 2023, after _Robert Israel_ *)
%Y A365342 Cf. A087704, A365343.
%K A365342 nonn
%O A365342 1,1
%A A365342 _Robert Israel_, Sep 01 2023
%E A365342 a(18)-a(21) from _Chai Wah Wu_, Sep 02 2023
%E A365342 a(22)-a(28) from _Martin Ehrenstein_, Sep 03 2023