A055517 - OEIS

%I #3 Mar 30 2012 17:30:21

%S 30,4,12,0,1,4,9,2,25,4,49,15,14,27,121,35,169,33,26,55,289,77,361,91,

%T 38,85,529,143,46,133,44,187,841,221,961,247,62,253,42,323,1369,217,

%U 74,391,1681,437,1849,403,86,493,2209

%N Largest integer k such that k | Phi(k) - d(k) + n, or 0 if no such k exists, where d() is the number of divisors.

%C In the case of n = 3, the condition is satisfied for all the primes.

%e for a(2), 12 | [ Phi(12) + d(12) + 2 ].

%Y Cf. A020488.

%K nonn

%O 0,1

%A _Robert G. Wilson v_, Jul 03 2000