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%I #21 Mar 14 2020 15:52:52
%S 0,3,5,6,9,30,33,36,39,53,60,63,65,66,90,95,96,99,105,120,172,175,177,
%T 178,180,209,240,243,277,300,303,306,330,340,343,360,363,366,390,396,
%U 399,430,480,483,485,486,533,534,543,571,600,603,605,606,630,633,636,658,660,663
%N Evil numbers (A001969) remaining evil if any digit is deleted (zeros allowed).
%C Dual variant of A248642.
%C Although for numbers >9 we never put 0 instead of the removed digit, we include single-digit numbers 0,3,5,6,9 since, e.g., 3=03, etc.
%e 172 is in the sequence since 172,72,12,17 are evil.
%o (Sage)
%o def is_evil(n):
%o if n==0:
%o return True
%o else:
%o return sum(Integer(n).digits(base=2))%2==0
%o def remain_evil(n):
%o if not(is_evil(n)):
%o return False
%o else:
%o L=Integer(n).digits(base=10)
%o M=[]
%o for i in [0..len(L)-1]:
%o G=L[0:i]+L[i+1:]
%o M.append(is_evil(sum(G[i]*10^i for i in [0..len(G)-1])))
%o return sum(M)==len(M)
%o [x for x in [0..500] if remain_evil(x)] # _Tom Edgar_, Oct 10 2014
%Y Cf. A001969, A248478, A248642, A248659.
%K nonn,base
%O 1,2
%A _Vladimir Shevelev_, Oct 10 2014
%E More terms from _Peter J. C. Moses_, Oct 10 2014
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