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A132416 Positive numbers which are powers of their last digit. 2
1, 2, 3, 4, 5, 6, 7, 8, 9, 25, 32, 36, 64, 125, 216, 243, 512, 625, 729, 1024, 1296, 3125, 7776, 8192, 15625, 16384, 16807, 19683, 32768, 46656, 59049, 78125, 131072, 262144, 279936, 390625, 1594323, 1679616, 1953125, 2097152, 4194304, 4782969 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Subsequence of A100753.

1, 5^k or 6^k for all k, 4^k or 9^k for all odd k, 2^k or 3^k or 7^k or 8^k for all k == 1 (mod 4). - Robert Israel, Apr 25 2017

LINKS

Robert Israel, Table of n, a(n) for n = 1..5993

EXAMPLE

9=9^1,25=5^2,32=2^5,36=6^2,64=4^3,125=5^3,216=6^3,243=3^5,512=2^9,625=5^4, etc.

MAPLE

N:= 10^9: # to get all terms <= N

S:= {1, seq(2^k, k=1..ilog2(N), 4), seq(3^k, k=1..floor(log[3](N)), 4),

     seq(4^k, k=1..floor(log[4](N)), 2), seq(5^k, k=1..floor(log[5](N))),

     seq(6^k, k=1..floor(log[6](N))), seq(7^k, k=1..floor(log[7](N)), 4),

     seq(8^k, k=1..floor(log[8](N)), 4), seq(9^k, k=1..floor(log[9](N)), 2)}:

sort(convert(S, list)); # Robert Israel, Apr 25 2017

MATHEMATICA

pldQ[n_]:=Module[{idn=IntegerDigits[n], lst}, lst=Last[idn]; lst>1&& IntegerQ[ Log[ lst, n]]]; Join[{1}, Select[Range[5*10^6], pldQ]] (* Harvey P. Dale, Jul 26 2014 *)

CROSSREFS

Cf. A100753

Sequence in context: A280249 A096867 A100753 * A128606 A085123 A131571

Adjacent sequences:  A132413 A132414 A132415 * A132417 A132418 A132419

KEYWORD

base,nonn

AUTHOR

Zak Seidov, Nov 13 2007

STATUS

approved

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Last modified September 28 17:43 EDT 2020. Contains 337393 sequences. (Running on oeis4.)