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%I #19 Apr 13 2024 14:57:44
%S 1,1,2,3,2,2,3,4,4,3,4,6,5,4,10,6,9,6,4,8,10,8,12,6,9,12,8,6,10,12,11,
%T 8,21,10,16,12,9,20,12,18,14,8,15,18,16,24,10,16,22,12,12,18,20,18,30,
%U 12,16,27,20,12,32,21,28,20,12,36,22,30,23,36,16,21,30,20,16,24,24,26
%N a(n) = H(A002808(n)) where H(n) is the half-totient function, H(n) = phi(n)/2: (A023022) and A002808(n) are the composites.
%H Harry J. Smith, <a href="/A062948/b062948.txt">Table of n, a(n) for n = 1..1000</a>
%o (PARI) H(n)=eulerphi(n)/2;
%o j=[]; for(n=2,200, if(isprime(n), n+1,j=concat(j,H(n) ))); j
%o (PARI) { n=0; for (m=2, 10^9, if (!isprime(m), write("b062948.txt", n++, " ", eulerphi(m)/2); if (n==1000, break)) ) } \\ _Harry J. Smith_, Aug 14 2009
%Y Cf. A023022, A002808.
%K easy,nonn
%O 1,3
%A _Jason Earls_, Jul 21 2001
%E Offset changed from 2 to 1 by _Harry J. Smith_, Aug 14 2009