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A385351
Perfect powers whose digits are all powers of the same single-digit base.
1
1, 4, 8, 9, 16, 81, 121, 128, 144, 441, 484, 841, 1331, 1444, 8281, 11881, 14884, 28224, 48841, 114244, 128881, 142884, 221841, 228484, 848241, 1121481, 1281424, 1418481, 2184484, 2214144, 8282884, 9393931, 11142244, 11282881, 18241441, 18818244, 18844281, 21242881
OFFSET
1,2
EXAMPLE
841 is a term since it is equal to 29^2 and its digits are all powers of 2: 8 = 2^3, 4 = 2^2, and 1 = 2^0;
1331 is a term since it is equal to 11^3 and its digits are all powers of 3: 1 = 3^0 and 3 = 3^1.
MATHEMATICA
perfectPowerQ[n_] := n == 1 || GCD @@ FactorInteger[n][[All, 2]] > 1; (* A001597 *)
nterms=20; list={}; len=0; n=1; While[len <=nterms, If[perfectPowerQ[n] &&(SubsetQ[{0}, dig=IntegerDigits[n]] || SubsetQ[{1, 2, 4, 8}, dig] || SubsetQ[{1, 3, 9}, dig] || SubsetQ[{1, 5}, dig] || SubsetQ[{1, 6}, dig] || SubsetQ[{1, 7}, dig]), AppendTo[list, n]; len++]; n++]; list
CROSSREFS
Cf. A001597, A385324 (supersequence).
Sequence in context: A202271 A334858 A162898 * A257009 A071592 A089765
KEYWORD
nonn,base
AUTHOR
Stefano Spezia, Jun 26 2025
STATUS
approved