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Primes p such that A001414(p-1) = A001414(p+1), where A001414 = sum of primes dividing n (with repetition).
8

%I #12 Dec 15 2017 17:36:32

%S 11,17,31,251,1429,3041,16561,16927,53299,56897,89783,95089,213599,

%T 282977,345547,432587,592223,763457,906949,915799,1050449,1058389,

%U 1485017,1577341,1678399,1780253,1855549,2131687,2374289,2658259

%N Primes p such that A001414(p-1) = A001414(p+1), where A001414 = sum of primes dividing n (with repetition).

%C Conjecture: sequence is infinite.

%H Charles R Greathouse IV, <a href="/A086711/b086711.txt">Table of n, a(n) for n = 1..1280</a>

%e a(3)=31 because it is prime and 30=2*3*5, 32=2^5 and 2+3+5 = 2+2+2+2+2 = 10.

%Y Cf. A001414, A190680.

%K nonn

%O 1,1

%A _Jason Earls_, Jul 28 2003