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%I #12 Sep 18 2013 12:04:51
%S 1,8,200,512,968,1458,3200,4232,5618,5832,6962,10368,16928,26912,
%T 36992,40328,53792,61952,84050,101250,110450,140450,147968,220448,
%U 247808,249218,253472,257762,279752,282752,320000,336200,344450,359552,361250,445568,472392,512072
%N Numbers n such that sigma(n) + tau(n) + phi(n) is a prime, where sigma(n) = A000203(n), tau(n) = A000005(n) and phi(n) = A000010(n).
%e sigma(200) = 465, tau(200) = 12, phi(200) = 80 and 465 + 12 + 80 = 557 is prime.
%p with(numtheory); P:=proc(q) local n; for n from 1 to q do
%p if isprime(sigma(n)+tau(n)+phi(n)) then print(n); fi; od; end: P(10^6);
%Y Cf. A000005, A000010, A000203, A009087, A023194, A038344, A055813, A062700, A064205, A115919, A141242, A229264, A229266-A229268.
%K nonn
%O 1,2
%A _Paolo P. Lava_, Sep 18 2013
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