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 A385739 #16 Jul 14 2025 16:42:59 %S A385739 5563,203431,389923,901423,5495263,7418863,28128367,188953969, %T A385739 210627577,392753209,402877087,505757683,619418689,2549153611, %U A385739 2580356851,3953660383,5692944349,6806206831,6894059071,7082199673,10058113363,11307503629,12601725943,12615171649 %N A385739 Primes p such that there exists a prime q < p such that sigma(q-1) = sigma(p+1) = p + q. %C A385739 The primes q and p form a P(-1, 1)-amicable pair. Apparently (q-1, p+1) is an amicable pair A259180. %H A385739 S. I. Dimitrov, <a href="https://arxiv.org/abs/2408.07387">Generalizations of amicable numbers</a>, arXiv:2408.07387 [math.NT], 2024. %e A385739 (5021, 5563) is such a pair because sigma(5021-1) = sigma(5563+1) = 5021 + 5563. %Y A385739 Cf. A000040, A000203, A063990, A008333, A259180, A385586, A385718. %K A385739 nonn,hard %O A385739 1,1 %A A385739 _S. I. Dimitrov_, Jul 08 2025 %E A385739 a(5)-a(13) from _Michel Marcus_, Jul 08 2025 %E A385739 a(14)-a(24) from _Giorgos Kalogeropoulos_, Jul 14 2025