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Numbers whose square and cube taken together contain each decimal digit.
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%I #20 Jun 28 2023 07:50:28

%S 69,128,203,302,327,366,398,467,542,591,593,598,633,643,669,690,747,

%T 759,903,923,943,1016,1018,1027,1028,1043,1086,1112,1182,1194,1199,

%U 1233,1278,1280,1282,1328,1336,1364,1396,1419,1459,1463,1467,1472,1475

%N Numbers whose square and cube taken together contain each decimal digit.

%C The first term, a(1) = 69, is the only number for which the square and the cube together contain each decimal digit 0 to 9 exactly once.

%C a(820) = 6534 is the only number of which the square and cube taken together contain each digit 0 to 9 exactly twice.

%H Robert G. Wilson v, <a href="/A363905/b363905.txt">Table of n, a(n) for n = 1..10000</a>

%H Harold Suarez, <a href="https://www.linkedin.com/feed/update/urn:li:activity:7073402002042417152">Interesting...</a>, Number Theory group on LinkedIn, June 2023.

%e 69^2 = 4761, 69^3 = 328509, which together contain each digit 0-9 exactly once.

%t fQ[n_] := Union[ Join[ IntegerDigits[n^2], IntegerDigits[n^3]]] == {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; Select[Range@1500, fQ] (* _Robert G. Wilson v_, Jun 27 2023 *)

%o (PARI) is(k)=#setunion(Set(digits(k^2)),Set(digits(k^3)))>9

%o select(is,[1..9999])

%o (Python)

%o from itertools import count, islice

%o def A363905_gen(startvalue=1): # generator of terms >= startvalue

%o return filter(lambda n:len(set(str(n**2))|set(str(n**3)))==10,count(max(startvalue,1)))

%o A363905_list = list(islice(A363905_gen(),20)) # _Chai Wah Wu_, Jun 27 2023

%Y Cf. A036744, A054038, A071519 and A156977 for "pandigital" squares.

%Y Cf. A119735: Numbers n such that every digit occurs at least once in n^3.

%K nonn,base,less

%O 1,1

%A _M. F. Hasler_, Jun 27 2023