A375754 - OEIS

%I #6 Aug 26 2024 16:55:21

%S 4,3,1,3,15,10,4,21,13,4,66,55,43,30,16,1,33,16,118,99,79,58,36,13,61,

%T 36,10,151,123,94,64,33,1,280,246,211,175,138,100,61,21,100,58,15,379,

%U 334,288,241,193,144,94,43,303,250,196,141,85,28,138,79,19,318,256

%N a(n) is the difference between the next greater square of a prime and n*(n+1)/2.

%e a(0) = A001248(1) - A000217(0) = 2^2 - 0 = 4,

%e a(1) = A001248(1) - A000217(1) = 2^2 - 1 = 3,

%e a(2) = A001248(1) - A000217(2) = 2^2 - 3 = 1,

%e a(3) = A001248(2) - A000217(3) = 3^2 - 6 = 3.

%o (PARI) a375754(n) = my(t=n*(n+1)/2, s=sqrtint(t), p=nextprime(s)); if(p^2-t < 0, p=nextprime(p+1)); p^2-t

%Y Cf. A000217, A001248, A075402, A375752, A375753.

%K nonn,easy

%O 0,1

%A _Hugo Pfoertner_, Aug 26 2024