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 A246972 #22 May 22 2025 10:21:40
%S A246972 10,41,94,169,2516,3625,4936,6449,8164,10081,121100,144121,169144,
%T A246972 196169,225196,256225,289256,324289,361324,400361,441400,484441,
%U A246972 529484,576529,625576,676625,729676,784729,841784,900841,961900,1024961,10891024,11561089,12251156,12961225,13691296
%N A246972 (n+1)^2 concatenated with n^2.
%H A246972 Vincenzo Librandi, <a href="/A246972/b246972.txt">Table of n, a(n) for n = 0..1000</a>
%t A246972 Table[FromDigits[Join[Flatten[IntegerDigits[{(n + 1)^2, n^2}]]]], {n, 0, 50}] (* _Vincenzo Librandi_, Sep 13 2014 *)
%t A246972 FromDigits/@(Join[IntegerDigits[#[[2]]],IntegerDigits[#[[1]]]]&/@ Partition[ Range[0,40]^2,2,1]) (* _Harvey P. Dale_, Apr 16 2015 *)
%o A246972 (Magma) [10] cat [Seqint(Intseq(n^2) cat Intseq(n^2+2*n+1)): n in [1..50]]; // _Vincenzo Librandi_, Sep 13 2014
%o A246972 (Python)
%o A246972 def A246972(n):
%o A246972 return int(str((n+1)**2)+str(n**2)) # _Chai Wah Wu_, Sep 13 2014
%Y A246972 Cf. A246973, A235497. For primes, see A104301.
%K A246972 nonn,base
%O A246972 0,1
%A A246972 _N. J. A. Sloane_, Sep 13 2014