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%I #53 Sep 21 2023 19:26:56
%S 1,2,3,5,6,9,11,15,17,21,24,29,30,39,41,51,54,59,66,75,77,87,96,105,
%T 107,120,129,137,141,161,165,180,186,201,209,221,227,249,255,270,285,
%U 306,311,324,336,359,366,390,401,420,435,459,465,495,501,527,534
%N Positions of records in A104706.
%C The entries in this sequence are the same as the partial sums of the independently derived A204539, for reasons unknown at present. - _Colm Fagan_, Jan 23 2012
%H Robert Israel, <a href="/A104738/b104738.txt">Table of n, a(n) for n = 1..5000</a>
%t A104706 = NestList[Rest[Insert[#, #[[1]], 2 + 2 #[[1]]]]&, Range[m = 1000], m][[All, 1]];
%t rec = 0; Reap[For[k = 1, k <= Length[A104706], k++, ak = A104706[[k]]; If[ak > rec, rec = ak; Sow[k]]]][[2, 1]] (* _Jean-François Alcover_, Apr 11 2019, after _Birkas Gyorgy_ in A104706 *)
%o (BASIC) n=n+1; temp1=n^2; for k=(n-1) step -1 to 2; temp2=int(temp1/k); temp1=k*temp2; if int((temp2+k)/2))*2<>(temp2+k) then temp1=temp1-k; next k; a(n-1)=temp1/4 ' _Colm Fagan_, Nov 08 2015
%o (PARI) a(n) = {n++; temp1 = n^2; forstep (k= n-1, 2, -1, temp2 = temp1\k; temp1 = k*temp2; if (((temp2+k)\2)*2 != (temp2+k), temp1 -= k)); temp1/4;} \\ after Basic; _Michel Marcus_, Dec 04 2015
%o (MATLAB)
%o function [ A ] = A104738( N )
%o % Produce a(1) : a(N)
%o M = N;
%o R = [1:M];
%o v = 1;
%o A = 1;
%o count = 1;
%o n = 1;
%o while count < N
%o n = n+1;
%o if 2*R(1)+1 > M
%o R = [R, (M+1):M+N];
%o end
%o R = [R(2:2*R(1)+1), R(1), R((2*R(1)+2) : M)];
%o if R(1) > v
%o A = [A, n];
%o v = R(1);
%o count = count+1;
%o end
%o end
%o end;
%o A104738(100)
%Y Cf. A104706, A104737, A104739, A204539.
%Y See A002491 for a conjectured connection to this sequence.
%K nonn
%O 1,2
%A _Zak Seidov_, Mar 21 2005
%E Extended by _Ray Chandler_, Jan 19 2012
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