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 A272386 #22 Feb 16 2025 08:33:34
%S A272386 13,59,79,97,107,127,157,269,337,347,439,457,479,563,601,631,719,743,
%T A272386 883,947,1021,1031,1049,1051,1061,1093,1109,1171,1201,1223,1499,1523,
%U A272386 1601,1669,1811,1901,1933,1997,2011,2053,2153,2207,2341,2399,2531,2539,2549,2551
%N A272386 Smallest primes of 5 X 5 magic squares formed from consecutive primes.
%C A272386 A necessary condition for a prime being in this sequence is that the sum of this and the subsequent 24 primes divided by 5 must be an odd integer. - _M. F. Hasler_, Oct 30 2018
%H A272386 Arkadiusz Wesolowski, <a href="/A272386/b272386.txt">Table of n, a(n) for n = 1..66</a>
%H A272386 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PrimeMagicSquare.html">Prime Magic Square</a>
%H A272386 Arkadiusz Wesolowski, <a href="/A272386/a272386.txt">Examples of these magic squares</a>
%H A272386 <a href="/index/Mag#magic">Index entries for sequences related to magic squares</a>
%e A272386 The smallest 5 X 5 magic square that can be formed from 25 consecutive primes consists of the primes 13 through 113, so the first term is 13:
%e A272386 n = 1
%e A272386 |----|----|----|----|----|
%e A272386 | 13 | 107| 73 | 101| 19 |
%e A272386 |----|----|----|----|----|
%e A272386 | 97 | 17 | 79 | 37 | 83 |
%e A272386 |----|----|----|----|----|
%e A272386 | 41 | 53 | 109| 43 | 67 |
%e A272386 |----|----|----|----|----|
%e A272386 | 103| 89 | 29 | 61 | 31 |
%e A272386 |----|----|----|----|----|
%e A272386 | 59 | 47 | 23 | 71 | 113|
%e A272386 |----|----|----|----|----|
%e A272386 The next smallest consists of the primes 59 through 179, so the second term is 59:
%e A272386 n = 2
%e A272386 |----|----|----|----|----|
%e A272386 | 59 | 163| 151| 137| 67 |
%e A272386 |----|----|----|----|----|
%e A272386 | 149| 61 | 79 | 109| 179|
%e A272386 |----|----|----|----|----|
%e A272386 | 113| 83 | 173| 107| 101|
%e A272386 |----|----|----|----|----|
%e A272386 | 167| 139| 71 | 127| 73 |
%e A272386 |----|----|----|----|----|
%e A272386 | 89 | 131| 103| 97 | 157|
%e A272386 |----|----|----|----|----|
%o A272386 (PARI) A272386(n)=MagicPrimes(A176571(n),5)[1] \\ See A073519 for MagicPrimes(). - _M. F. Hasler_, Oct 28 2018
%o A272386 (PARI) is_candidate(p)={denominator(p=A173981(,p))==1 && bittest(p,0)} \\ For p < 167, this yields exactly the terms of A272386. Exceptions (primes satisfying this but not in A272386) are (167, 227, 383, 461, 607, ...). - _M. F. Hasler_, Oct 30 2018
%Y A272386 Cf. A176571, A256891, A260673, A272387.
%K A272386 nonn
%O A272386 1,1
%A A272386 _Arkadiusz Wesolowski_, Apr 28 2016