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%I #5 Apr 04 2023 22:10:27
%S 1,5,6,11,76,105,501,505,506,605,756,826,1001,5941,10005,10505,12731,
%T 13921,50001,50005,50006,50105,50501,50505,50506,50605,60005,60505,
%U 88705,100001,118905,364231,592421,594941,684006,1000005,1000505,1050005,1050505,1355941
%N 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 Subsequence of A326418. No term starts with the digit 2.
%o (Python)
%o from itertools import count, islice
%o def A362020_gen(startvalue=0): # generator of terms >= startvalue
%o 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_list = list(islice(A362020_gen(),50))
%Y Cf. A326418.
%K nonn,base
%O 1,2
%A _Chai Wah Wu_, Apr 04 2023