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%I #12 Dec 29 2023 10:33:55
%S 1,4,10,16,22,28,30,40,46,52,58,60,70,72,82,88,100,106,112,130,136,
%T 138,148,150,156,166,172,178,180,190,196,198,210,226,232,238,240,250,
%U 256,262,268,270,280,282,292,310,316,330,336,346,352,358,366,372,382,388
%N a(n) = phi(A067775(n)).
%C Count of numbers smaller than and coprime to p for primes p such that p + 4 is composite.
%C Subsequence of A006093.
%o (PARI) {forprime(p=2, 400, if(!isprime(p+4), print1(eulerphi(p), ",")))} \\ _Klaus Brockhaus_, Aug 31 2008
%Y Cf. A067775, A000010 (Euler totient function), A006093 (primes minus 1), A141426, A141515.
%K nonn
%O 1,2
%A _Giovanni Teofilatto_, Aug 06 2008
%E More terms from _Robert G. Wilson v_, Aug 18 2008
%E Edited by _N. J. A. Sloane_ and _Klaus Brockhaus_, Aug 31 2008