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%I #9 Aug 04 2015 23:43:16
%S 2,7,61,211
%N Primes which have no representation p + k*(k+1) / 2, with p prime and k > 0: A000040-Complement of A065396.
%C Finite? (Checked up to A000040(100000) = 1299709.)
%C Next term > 7000000. - _R. J. Mathar_, Apr 23 2006
%C No other terms less than 2*10^9. - _T. D. Noe_, Mar 26 2008
%p for n from 1 to 7000000 do if isprime(n) = true then foundp := false ; for k from 1 to n do if isprime(n-k*(k+1)/2) = true then foundp := true ; break ; elif n-k*(k+1)/2 < 2 then break ; fi ; od ; if foundp = false then print(n) ; fi ; fi ; od : # _R. J. Mathar_, Apr 23 2006
%Y Cf. A000040, A000217, A065377, A065396.
%K more,nonn
%O 1,1
%A _Reinhard Zumkeller_, Nov 05 2001
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