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%I #15 Mar 14 2020 05:05:57
%S 2,6,9,940
%N Numbers k such that k^k is the average of its nearest 2 primes.
%F A333184(a(n)) = 0.
%F A074966(a(n)) = A074967(a(n)).
%e Previous P k^k Next P
%e a(n) A098681(a(n)) A000312(a(n)) A098682(a(n))
%e 2 3 4 5
%e 6 46649 46656 46663
%e 9 387420479 387420489 387420499
%e 940 940^940-3063 940^940 940^940+3063
%o (PARI) isok(k) = if (k>1, my(x=k^k); precprime(x-1)+nextprime(x+1) == 2*x); \\ _Michel Marcus_, Mar 14 2020
%Y Cf. A000312, A074966, A074967, A098681, A098682, A161503, A333184.
%K nonn,bref,hard,more
%O 1,1
%A _Hugo Pfoertner_, Mar 11 2020