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%I #16 Aug 18 2017 03:13:28
%S 10011001,10025001,10052001,10088001,10100101,10111101,10125101,
%T 11011011,11025011,11052011,11088011,11100111,11111111,11125111,
%U 12011051,12025051,12052051,12088051,12100151,12111151,12125151,15011021,15025021,15052021
%N Vertically symmetrical dates DDMMYYYY excluding years which are divisible by 10, considered as numbers, in increasing order.
%C 2 and 5 are taken as mirror images (as on calculator displays). a(1)=10011001, a(13)=11111111 and a(38)=20052005 (May 20 2005!) also share the unique property of having two symmetrical halves.
%C This sequence has exactly 70 terms, ending with 28125185 (Dec 28 5185).
%H Nathaniel Johnston, <a href="/A106605/b106605.txt">Table of n, a(n) for n = 1..70</a> (full sequence)
%p compdig := proc(n) if(n=2)then return 5: elif(n=5)then return 2: elif(n=0 or n=1 or n=8)then return n: else return -1: fi: end: for d from 10 to 28 do for m from 1 to 12 do for y from 1 to 8888 do dt:=1000000*d+10000*m+y: dig:=convert(dt,base,10): if(dig[1]=compdig(dig[8]) and dig[2]=compdig(dig[7]) and dig[3]=compdig(dig[6]) and dig[4]=compdig(dig[5]))then print(dt): fi: od: od: od: # _Nathaniel Johnston_, May 17 2011
%Y Cf. A053701.
%K base,easy,fini,full,nonn
%O 1,1
%A Nicolas Graner, _Eric Angelini_ and _Alexandre Wajnberg_, May 10 2005
%E Definition clarified by _Hieronymus Fischer_, Apr 01 2012