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%I #13 Nov 11 2020 11:58:34
%S 0,1,8,10,21,39,54,58,61,135,134,213,217,259,267,449,413,530,645,471,
%T 661,734,741,1029,1194,1257,1219,1434,1372,1456,1547,1939,2007,1987,
%U 2471,2319,2802,2610,2564,3334,3548,3684,3612,3576,4399,3686,5071,4810,4647,5066,6035,5213,5890,6335,6327
%N a(n) = Sum_{i=1..n-1} (prime(i)^2 mod prime(n)).
%C The sequence is not monotone, and not one-to-one: a(95)=a(97)=23038.
%H Robert Israel, <a href="/A338820/b338820.txt">Table of n, a(n) for n = 1..10000</a>
%e The first three primes are 2, 3, 5, so a(3) = (2^2 mod 5) + (3^2 mod 5) = 4 + 4 = 8.
%p P:= [seq(ithprime(i),i=1..100)]:
%p seq(add(P[i]^2 mod P[n],i=1..n-1),n=1..100);
%o (PARI) a(n) = my(p=prime(n)); sum(i=1, n-1, lift(Mod(prime(i), p)^2)); \\ _Michel Marcus_, Nov 11 2020
%Y Cf. A338102, A338821.
%K nonn
%O 1,3
%A _J. M. Bergot_ and _Robert Israel_, Nov 10 2020