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%I #9 Jan 06 2019 06:06:55
%S 1,8,12,15,24,25,30,32,33,35,36,39,40,42,44,48,50,51,54,56,60,63,65,
%T 66,68,69,72,78,80,81,84,85,87,90,92,96,98,100,102,105,108,112,114,
%U 116,117,120,121,123,126,128,129,130,132,136,138,140,141,143,144,148,150,153
%N Numbers k such that the deficiency of k plus the number of proper divisors of k is not a prime number (see A152864).
%p with(numtheory): a := proc (n) if isprime(2*n-sigma(n)+tau(n)-1) = false then n else end if end proc: seq(a(n), n = 1 .. 200); # _Emeric Deutsch_, Jan 08 2009
%Y Cf. A000005, A000040, A000203, A032741, A033879, A152757, A152770, A152864.
%K easy,nonn
%O 1,2
%A _Omar E. Pol_, Dec 14 2008
%E Extended by _Emeric Deutsch_, Jan 08 2009
%E Name edited by _Jon E. Schoenfield_, Jan 06 2019