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%I #15 Mar 04 2023 11:46:51
%S 83338,1142411,1571751,1587851,2013102,2081802,2541452,3278723,
%T 3394933,3433343,3863683,4684864,5067605,5516155,5985895,6148416,
%U 6467646,6771776,6912196,7043407,7136317,7304037,7417147,7605067,7987897
%N Palindromic Super-4 Numbers.
%D C. A. Pickover, "Keys to Infinity", New York: Wiley, p. 7, 1995.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Super-dNumber.html">Super-d Number</a>.
%t Select[Range[80*10^5],PalindromeQ[#]&&SequenceCount[IntegerDigits[4#^4],{4,4,4,4}]>0&] (* _Harvey P. Dale_, Jan 18 2023 *)
%Y Cf. A014569, A032744.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, May 15 1998