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%I #17 Dec 24 2014 00:16:54
%S 1,3,4,5,11,15,17,27,29,33,39,41,55,57,59,64,69,71,85,93,100,101,105,
%T 107,123,133,137,145,149,159,165,175,177,179,187,189,191,197,219,227,
%U 231,235,237,239,245,247,253,255,259,265,267,269,273,275,281,285,303
%N Numbers n such that n + number of divisors is a prime.
%C Smaller of the twin primes (A001359) is a term.
%H Michael De Vlieger, <a href="/A067532/b067532.txt">Table of n, a(n) for n = 1..10000</a>
%e a(1)=1 (1+d(1)=1+1=2=prime); a(2)=3 (3+d(3)=3+2=5=prime).
%p with(numtheory): for n from 3 to 500 do if isprime(n+tau(n)) then printf(`%d,`,n) fi:od: # _James A. Sellers_, Feb 18 2002
%t a067532[n_] := Select[Range[n], PrimeQ[# + DivisorSigma[0, #]] &]; a067532[303] (* _Michael De Vlieger_, Dec 22 2014 *)
%Y Cf. A000005, A001359, A067531.
%K easy,nonn
%O 1,2
%A _Amarnath Murthy_, Feb 17 2002
%E More terms from _James A. Sellers_, Feb 18 2002
%E Sequence corrected by _Juri-Stepan Gerasimov_, Oct 18 2009
%E Offset corrected by _N. J. A. Sloane_, Oct 21 2009
%E Corrected by _Charles R Greathouse IV_, Mar 19 2010