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A061108 Compute Euler totient function for the prime(n+1)-prime(n)-1 composite numbers between two consecutive primes; choose the largest. 2

%I

%S 2,2,6,4,8,6,12,20,8,24,24,12,24,42,40,16,48,44,24,60,54,64,72,60,32,

%T 52,36,72,110,84,108,44,120,40,120,132,82,156,120,48,160,64,96,60,180,

%U 192,120,72,120,184,64,216,220,216,208,72,200,180,92,272,264,204,96

%N Compute Euler totient function for the prime(n+1)-prime(n)-1 composite numbers between two consecutive primes; choose the largest.

%H Harry J. Smith, <a href="/A061108/b061108.txt">Table of n, a(n) for n = 2..1000</a>

%F a(n) = Max{Phi(c); prime(n+1) > c > prime(n)}.

%o (PARI) { n=1; q=3; forprime (p=5, prime(1003), a=0; for (i=q + 1, p - 1, a=max(eulerphi(i), a)); q=p; write("b061108.txt", n++, " ", a) ) } \\ _Harry J. Smith_, Jul 18 2009]

%Y Cf. A000010, A061106.

%K nonn

%O 2,1

%A _Labos Elemer_, May 29 2001

%E Offset corrected by _Michel Marcus_, Mar 21 2018

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Last modified April 21 17:36 EDT 2021. Contains 343156 sequences. (Running on oeis4.)