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%I #38 Apr 04 2024 10:34:01
%S 0,1,4,5,6,9,10,24,25,32,40,49,50,51,56,60,75,76,90,99,100,125,240,
%T 249,250,251,375,376,400,490,499,500,501,510,600,624,625,749,750,751,
%U 760,782,875,900,990,999,1000,1249,1250,2400,2490,2500,2510
%N Numbers k such that the decimal expansion of k^3 contains k as a substring.
%H Giovanni Resta, <a href="/A029942/b029942.txt">Table of n, a(n) for n = 1..1000</a> (first 500 terms from Reinhard Zumkeller)
%e 24 is a term as 24^3 = 13824 contains 24 as a substring.
%e 250 is a term as 250^3 = 1562500 contains 250 as a substring.
%e 6^3 = 21_6, 782^3 = 4_782_11768.
%t n3ssQ[n_]:=Module[{idn=IntegerDigits[n],idn3=Partition[ IntegerDigits[ n^3], IntegerLength[n],1]},MemberQ[idn3,idn]]; Join[{0},Select[Range[ 2600],n3ssQ]] (* _Harvey P. Dale_, Jan 23 2012 *)
%t Select[Range[0,2600],SequenceCount[IntegerDigits[#^3],IntegerDigits[ #]]> 0&] (* _Harvey P. Dale_, Aug 29 2021 *)
%o (Haskell)
%o import Data.List (isInfixOf)
%o a029942 n = a029942_list !! (n-1)
%o a029942_list = [x | x <- [0..], show x `isInfixOf` show (x^3)]
%o -- _Reinhard Zumkeller_, Feb 29 2012
%Y Cf. A018834 (squares), A075904 (4th powers), A075905 (5th powers), A136490 (base 2).
%Y Cf. A000578. Supersequence of A029943.
%K nonn,base,nice
%O 1,3
%A _Patrick De Geest_
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