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 A362020 #5 Apr 04 2023 22:10:27
%S A362020 1,5,6,11,76,105,501,505,506,605,756,826,1001,5941,10005,10505,12731,
%T A362020 13921,50001,50005,50006,50105,50501,50505,50506,50605,60005,60505,
%U A362020 88705,100001,118905,364231,592421,594941,684006,1000005,1000505,1050005,1050505,1355941
%N A362020 Nonnegative numbers k not ending in 0 such that, in decimal representation, the subsequence of digits of k^2 occupying an odd position is equal to the digits of k.
%C A362020 Subsequence of A326418. No term starts with the digit 2.
%o A362020 (Python)
%o A362020 from itertools import count, islice
%o A362020 def A362020_gen(startvalue=0): # generator of terms >= startvalue
%o A362020 return filter(lambda n:n%10 and n==int(''.join((s:=str(n**2))[len(s)&1^1::2])),count(max(startvalue,0)))
%o A362020 A362020_list = list(islice(A362020_gen(),50))
%Y A362020 Cf. A326418.
%K A362020 nonn,base
%O A362020 1,2
%A A362020 _Chai Wah Wu_, Apr 04 2023