This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
a(5) = 1019 as 1019 + 5 = 1024 = 4^5.
1^prime(1)+prime(1) = 1^2+2 = 3 is prime, hence a(1) = 1. 1^prime(2)+prime(2) = 1^3+3 = 4 is not prime, but 2^prime(2)+prime(2) = 2^3+3 = 11 is prime, hence a(2) = 2. k^prime(4)+prime(4) is not prime for k < 16, but 16^prime(4)+prime(4) = 16^7+7 = 268435463 is prime, hence a(4) = 16. a(18)^prime(18)+prime(18) = 1348^61+61 has 191 digits.
a177832(n) = {local(k=1, p=prime(n)); while(!isprime(k^p+p), k+=1); k}
1^prime(1)-prime(1) = 1^2-2 = -1 is not prime, but 2^prime(2)-prime(2) = 2^2-2 = 2 is prime, hence a(1) = 2. k^prime(4)-prime(4) is not prime for k < 60, but 60^prime(4)-prime(4) = 60^7-7 = 2799359999993 is prime, hence a(4) = 60. a(19)^prime(19)-prime(19) = 462^67-67 has 179 digits.
a177956(n) = {local(k=1, p=prime(n)); while(!isprime(k^p-p), k+=1); k}
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