cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A029780 Numbers k such that every digit that appears in k also appears at least once in both k^2 and k^3.

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%I A029780 #14 Apr 03 2023 18:23:56
%S A029780 0,1,5,6,10,11,25,50,55,60,64,66,76,99,100,101,110,111,112,115,116,
%T A029780 125,225,250,275,288,323,376,405,499,500,501,502,525,550,555,600,602,
%U A029780 625,640,642,644,660,666,676,724,726,733,755,760,776,777,833
%N A029780 Numbers k such that every digit that appears in k also appears at least once in both k^2 and k^3.
%H A029780 Harvey P. Dale, <a href="/A029780/b029780.txt">Table of n, a(n) for n = 1..1000</a>
%F A029780 A029772 intersect A029776. - _Sean A. Irvine_, Mar 04 2020
%t A029780 Select[Range[0,1000],Min[DigitCount[#^2,10,IntegerDigits[#]]]>0 && Min[ DigitCount[ #^3,10, IntegerDigits[#]]]>0&] (* _Harvey P. Dale_, Aug 12 2016 *)
%o A029780 (Python)
%o A029780 from itertools import count, islice
%o A029780 def A029780_gen(startvalue=0): # generator of terms >= startvalue
%o A029780     return filter(lambda n:set(str(n)) <= set(str(m:=n**2)) & set(str(n*m)), count(max(startvalue,0)))
%o A029780 A029780_list = list(islice(A029780_gen(),20)) # _Chai Wah Wu_, Apr 03 2023
%Y A029780 Cf. A029772, A046827.
%K A029780 nonn,base
%O A029780 1,3
%A A029780 _Patrick De Geest_