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a(n) = Sum_{k=1..n} prime(n)^prime(k).
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%I #25 Dec 06 2021 01:46:57

%S 4,36,3275,840742,285331320285,304667330108466,827250200736677741479,

%T 1983900084687573008820254,20880542756369384174903669400953,

%U 2567686157477937962829648585022637187631942,17086936018496343189927728440572423322828545911

%N a(n) = Sum_{k=1..n} prime(n)^prime(k).

%e For n=3, p=5, a(n) = 5^2 + 5^3 + 5^5 = 25 + 125 + 3125 = 3275.

%o (PARI) a(n) = my(p=prime(n)); sum(k=1, n, p^prime(k)); \\ _Michel Marcus_, Dec 02 2021

%o (Python)

%o from sympy import prime, primerange

%o def a(n): pn = prime(n); return sum(pn**pk for pk in primerange(1, pn+1))

%o print([a(n) for n in range(1, 12)]) # _Michael S. Branicky_, Dec 02 2021

%K nonn

%O 1,1

%A _Firdous Ahmad Mala_, Dec 02 2021

%E More terms from _Michel Marcus_, Dec 02 2021