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 A021387 #24 Aug 07 2025 14:40:15
%S A021387 0,0,2,6,1,0,9,6,6,0,5,7,4,4,1,2,5,3,2,6,3,7,0,7,5,7,1,8,0,1,5,6,6,5,
%T A021387 7,9,6,3,4,4,6,4,7,5,1,9,5,8,2,2,4,5,4,3,0,8,0,9,3,9,9,4,7,7,8,0,6,7,
%U A021387 8,8,5,1,1,7,4,9,3,4,7,2,5,8,4,8,5,6,3,9,6,8,6,6,8,4,0,7,3,1,0
%N A021387 Decimal expansion of 1/383.
%C A021387 The magic square that uses the decimals of 1/383 is fully magic. 19 has the same property (see A021023). For other such primes see A072359. - _Michel Marcus_, Sep 02 2015
%H A021387 Wikipedia, <a href="https://en.wikipedia.org/wiki/Prime_reciprocal_magic_square">Prime reciprocal magic square</a>
%t A021387 x = RealDigits[N[1/383, 120]]; Table[0, {Abs@ Last@ x}]~Join~First@ x (* _Michael De Vlieger_, Sep 02 2015 *)
%t A021387 realDigitsRecip[383] (* The realDigitsRecip program is at A021200 *) (* _Harvey P. Dale_, Aug 07 2025 *)
%o A021387 (PARI) default(realprecision,2000);1/383.0 \\ _Anders Hellström_, Sep 02 2015
%Y A021387 Cf. A021023, A072359.
%K A021387 nonn,cons
%O A021387 0,3
%A A021387 _N. J. A. Sloane_