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A361639 For n > 1, A359804(n) is a multiple of A361503(n-1); a(n) = A359804(n) / A361503(n-1).

%I A361639 #10 Mar 19 2023 17:46:35
%S A361639 1,1,1,2,2,2,1,3,4,3,2,1,4,4,3,2,5,6,4,6,3,5,8,8,8,6,4,9,7,13,9,10,8,
%T A361639 12,11,9,16,12,10,6,1,13,17,13,15,19,11,16,16,12,8,17,17,23,18,13,9,
%U A361639 26,19,18,14,20,19,15,29,10,23,16,23,24,17,24,11,18
%N A361639 For n > 1, A359804(n) is a multiple of A361503(n-1); a(n) = A359804(n) / A361503(n-1).
%H A361639 Michael De Vlieger, <a href="/A361639/b361639.txt">Table of n, a(n) for n = 2..16384</a>
%H A361639 Rémy Sigrist, <a href="/A361639/a361639.txt">C program</a>
%H A361639 Michael De Vlieger, <a href="/A361639/a361639.png">Log log scatterplot of a(n)</a>, n = 2..2^20, showing 1s in red. Index on x-axis is n-1.
%e A361639 a(10) = A359804(10) / A361503(9) = 8 / 2 = 4.
%t A361639 nn = 120; c[_] = False; q[_] = 1;
%t A361639 i = 1; j = 2; c[1] = c[2] = True; u = 3;
%t A361639 {1}~Join~Reap[Do[
%t A361639      (m = q[#]; While[c[m #], m++]; k = m #; q[#] = m) &[(p = 2;
%t A361639        While[Divisible[i j, p], p = NextPrime[p]]; p)]; Sow[m];
%t A361639      Set[{c[k], i, j}, {True, j, k}];
%t A361639 If[k == u, While[c[u], u++]], {n, 3, nn}] ][[-1, -1]] (* _Michael De Vlieger_, Mar 19 2023 *)
%o A361639 (C) See Links section.
%Y A361639 Cf. A359804, A361503.
%K A361639 nonn
%O A361639 2,4
%A A361639 _Rémy Sigrist_, Mar 19 2023