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%I #20 Mar 03 2023 06:02:09
%S 0,3,5,12,10,3,5,20,18,3,9,24,18,6,5,17,48,34,3,9,40,36,7,65,72,10,3,
%T 33,96,66,11,129,132,6,3,17,80,68,5,257,258,130,129,33,34,6,13,513,
%U 514,1026,1025,9,14,2050,2049,65,66,4098,4097,5,260,264,11,7
%N The binary expansion of a(n) specifies which primes divide A360519(n).
%H Rémy Sigrist, <a href="/A361111/b361111.txt">Table of n, a(n) for n = 1..10000</a>
%H Rémy Sigrist, <a href="/A361111/a361111.gp.txt">PARI program</a>
%H N. J. A. Sloane, <a href="/A360519/a360519.pdf">Table showing A360519(1)-A360519(13)</a>, also the smallest missing number (smn, A361109 and A361110), binary vectors showing which terms are divisible by the primes 2, 3, 5, 7, 11; and phi, a decimal representation of those binary vectors (A361111). This sequence forms the bottom row of the table.
%F a(n) = A087207(A360519(n)). - _Rémy Sigrist_, Mar 03 2023
%e A360519(6) = 12, which is divisible by 2, 3, but not 5, 7, 11, ... So we write down 1, 1, 0, 0, 0, .... Thus a(6) has binary expansion ...00011, and so a(6) = 3.
%o (PARI) See Links section.
%Y Cf. A087207, A360519.
%K nonn,base
%O 1,2
%A _Scott R. Shannon_ and _N. J. A. Sloane_, Mar 03 2023
%E More terms from _Rémy Sigrist_, Mar 03 2023