A302043 - OEIS

%I #7 Apr 05 2018 20:33:31

%S 0,1,2,2,4,3,6,4,6,5,10,6,12,7,10,8,16,9,18,10,12,11,22,12,20,13,20,

%T 14,28,15,30,16,18,17,28,18,36,19,28,20,40,21,42,22,24,23,46,24,42,25,

%U 26,26,52,27,30,28,30,29,58,30,60,31,50,32,54,33,66,34,36,35,70,36,72,37,58,38,66,39,78,40,42,41,82,42,50,43,52,44,88,45,42

%N a(n) = n - A302042(n); an analog of A060681 based on the sieve of Eratosthenes (A083221).

%C An analog of A060681 based on the sieve of Eratosthenes (A083221).

%H Antti Karttunen, <a href="/A302043/b302043.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Si#sieve">Index entries for sequences generated by sieves</a>

%F a(n) = n - A302042(n).

%o (PARI)

%o A302042(n) = if(1==n,n,my(k=0); while((n%2), n = A268674(n); k++); n = n/2; while(k>0, n = A250469(n); k--); (n));

%o A302043(n) = (n - A302042(n));

%Y Cf. A060681, A302042.

%K nonn

%O 1,3

%A _Antti Karttunen_, Mar 31 2018