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A175031 Sequence of increasing positive perfect powers such that neighboring digits in the sequence are distinct. 0
1, 4, 8, 9, 16, 25, 27, 32, 36, 49, 64, 81, 216, 243, 256, 289, 324, 343, 484, 512, 529, 576, 729, 784, 841, 961, 2025, 2048, 2187, 2197, 2304, 2401, 2601, 2704, 2809, 2916, 3025, 3125, 3136, 3249, 3481, 3721, 3969, 4096, 4356, 4624, 5041, 5184, 5329, 5476 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Subsequence of A090516 (Perfect powers (at least a square) in which neighboring digits are distinct.) which itself is subsequence of A001597 ( Perfect powers: m^k where m is an integer and k >= 2) which itself is Subsequence of A000027 (natural numbers).
LINKS
MATHEMATICA
m=26000; a=1; A001597=Union[Join[{a}, Flatten[Table[n^i, {n, 2, Sqrt[m]}, {i, 2, Log[n, m]}]]]]; A090516=Select[A001597, Max[Length/@Split[IntegerDigits[ # ]]]==1&]; S={1}; ia1={a}; Do[si=A090516[[i]]; If[IntegerDigits[si][[1]]!=ia1, AppendTo[S, si]; ia1=IntegerDigits[si][[ -1]]], {i, 2, Length[se1]}]; S
CROSSREFS
Sequence in context: A090516 A090515 A075309 * A052054 A046447 A087244
KEYWORD
base,nonn
AUTHOR
Zak Seidov, Nov 06 2009
STATUS
approved

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Last modified June 19 16:49 EDT 2024. Contains 373503 sequences. (Running on oeis4.)