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 A072387 #20 Nov 27 2021 15:36:23 %S A072387 1,10,190,11026,11476,12880,13366,19306,21115,23005,26335,28441,36046, %T A072387 53956,54946,58996,60031,65341,68635,70876,72010,83845,91378,1030330, %U A072387 1047628,1095940,1100386,1154440,1205128,1209790,1223830,1242676,1247410,1266436,1285606 %N A072387 Triangular number x such that x + reverse of x is a prime. %H A072387 Amiram Eldar, <a href="/A072387/b072387.txt">Table of n, a(n) for n = 1..10000</a> %e A072387 10 is a term because it is a triangular number and 10 + 01 = 11 is a prime. %t A072387 tri[n_] := n*(n + 1)/2; tri /@ Select[Range[10^3], PrimeQ[(t = tri[#]) + FromDigits @ Reverse @ IntegerDigits[t]] &] (* _Amiram Eldar_, Aug 24 2020 *) %t A072387 Select[Accumulate[Range[2000]],PrimeQ[#+IntegerReverse[#]]&] (* _Harvey P. Dale_, Nov 27 2021 *) %o A072387 (PARI) isok(n) = ispolygonal(n, 3) && isprime(n+subst(Polrev(digits(n)), x, 10)); \\ _Michel Marcus_, Nov 29 2014 %Y A072387 Intersection of A000217 and A072366. - _Michel Marcus_, Nov 29 2014 %Y A072387 Cf. A056964. %K A072387 base,nonn %O A072387 1,2 %A A072387 _Shyam Sunder Gupta_, Jul 20 2002 %E A072387 More terms from _Michel Marcus_, Nov 29 2014