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%I #12 Aug 25 2019 13:49:04
%S 1,0,7,7,8,9,10,10,10,10,12,12,12,12,13,13,13,14,15,16,16,16,16,16,17,
%T 17,17,18,19,19,19,20,20,20,21,22,22,22,22,23,23,24,24,24,24,25,25,25,
%U 25,25,26,26,27,28,28,28,30,30,30,31,31,31,31,31,31,31,31,31,31,31,32
%N a(n) = A050435(n) mod A002808(n).
%C Original name: Remainder when 2nd order composite, A050435(n), is divided by first order composite, A002808(n). - _Michael De Vlieger_, Dec 09 2018
%H Michael De Vlieger, <a href="/A076236/b076236.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A050435(n) mod A002808(n).
%e Let c(n) be the n-th composite number. a(1) = 1 since c(c(1)) mod c(1) = c(4) mod 4 = 9 mod 4 = 1. a(2) = 0 since c(c(2)) mod c(2) = c(6) mod 6 = 12 mod 6 = 0. - _Michael De Vlieger_, Dec 09 2018
%t c[n_] := FixedPoint[n + PrimePi[#] + 1 &, n + PrimePi[n] + 1]; Array[Mod[c@ c@ #, c@ #] &, 71] (* _Michael De Vlieger_, Dec 09 2018, after _Robert G. Wilson v_ at A002808 *)
%Y Cf. A002808, A050435-A050439, A065860, A076237-A076239.
%K nonn
%O 1,3
%A _Labos Elemer_, Oct 08 2002
%E Edited by _Michael De Vlieger_, Dec 09 2018