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A153806 Strobogrammatic cyclops numbers.

%I A153806 #14 May 22 2025 10:21:35
%S A153806 0,101,609,808,906,11011,16091,18081,19061,61019,66099,68089,69069,
%T A153806 81018,86098,88088,89068,91016,96096,98086,99066,1110111,1160911,
%U A153806 1180811,1190611,1610191,1660991,1680891,1690691,1810181,1860981
%N A153806 Strobogrammatic cyclops numbers.
%C A153806 Intersection of A000787 and A134808.
%H A153806 Kenny Lau, <a href="/A153806/b153806.txt">Table of n, a(n) for n = 1..20000</a>
%e A153806 1680891 is a member because it is the same upside down (A000787) and also a cyclops number (A134808).
%t A153806 Select[Range[10^7], And[OddQ@ Length@#, Part[#, Ceiling[Length[#]/2]] == 0, Times @@ Boole@ Map[MemberQ[{0, 1, 6, 8, 9}, #] &, Union@ #] == 1, Count[#, 0] == 1, (Take[#, Floor[Length[#]/2]] /. {6 -> 9, 9 -> 6}) ==
%t A153806 Reverse@ Take[#, -Floor[Length[#]/2]]] &@ IntegerDigits@ # &] (* _Michael De Vlieger_, Jul 05 2016 *)
%o A153806 (Python)
%o A153806 import sys
%o A153806 f = open('b153806.txt', 'w')
%o A153806 i = 1
%o A153806 n = 0
%o A153806 a = [""]
%o A153806 r = [""]  #reversed strobogrammatically
%o A153806 while True:
%o A153806     for x,y in zip(a,r):
%o A153806         f.write(str(i)+" "+x+"0"+y+"\n")
%o A153806         i += 1
%o A153806         if i>20000:
%o A153806             f.close()
%o A153806             sys.exit()
%o A153806     a = sum([[x+"1",x+"6",x+"8",x+"9"] for x in a],[])
%o A153806     r = sum([["1"+x,"9"+x,"8"+x,"6"+x] for x in r],[])
%o A153806 # _Kenny Lau_, Jul 05 2016
%Y A153806 Cf. A000787, A007597, A134808, A134809, A138131, A138148, A153807.
%K A153806 base,easy,nonn
%O A153806 1,2
%A A153806 _Omar E. Pol_, Jan 15 2009
%E A153806 Extended beyond 11011 by _R. J. Mathar_, Jan 17 2009