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.
%I A381020 #10 Feb 13 2025 12:21:07 %S A381020 30,45,60,75,92,106,119,133,141,157,170,177,185,204,224,236,245,260, %T A381020 275,292,305,318,330,342,359,371,382,390,405,419,430,444,457,472,490, %U A381020 507,524,535,550,561,570,583,593,604,611,621,627,638,647,659,670,679,683,697 %N A381020 a(n) = A381018(100*n). %H A381020 Thomas Ehrenborg, <a href="https://arxiv.org/abs/2502.06804">Gauss Circle Primes</a>, arXiv:2502.06804 [math.GM], 2025. See Table 2 p. 4. %o A381020 (Python) %o A381020 from math import isqrt %o A381020 from sympy import isprime %o A381020 def A381020(n): return sum(1 for m in range(1,100*n+1) if isprime(1+(sum(isqrt(k*((m<<1)-k)) for k in range(1,m+1))<<2))) # _Chai Wah Wu_, Feb 13 2025 %Y A381020 Cf. A028505, A381018. %K A381020 nonn %O A381020 1,1 %A A381020 _Michel Marcus_, Feb 12 2025 %E A381020 More terms from _Jinyuan Wang_, Feb 13 2025