|
| |
|
|
A047726
|
|
Number of different numbers that are formed by permuting digits of n.
|
|
8
| |
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 3, 3, 6
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,10
|
|
|
LINKS
| A. Dunigan AtLee, Table of n, a(n) for n = 1..100000.
|
|
|
FORMULA
| a(n) << n / (log_10 n)^4.5 by Stirling's approximation. [Charles R Greathouse IV, Sep 29 2011]
|
|
|
EXAMPLE
| From 102 we get 102 120 210 201 12 and 21, so a(102)=6.
|
|
|
MATHEMATICA
| pd[n_]:=Module[{p=Permutations[IntegerDigits[n]]}, Length[Union [FromDigits/@p]]]; pd/@Range[120] (* From Harvey P. Dale, Mar 22 2011 *)
|
|
|
PROG
| (Haskell)
import Data.List (permutations, nub)
a047726 n = length $ nub $ permutations $ show n
-- Reinhard Zumkeller, Jul 26 2011
(PARI) a(n)=n=eval(Vec(Str(n))); (#n)!/prod(i=0, 9, sum(j=1, #n, n[j]==i)!) \\ Charles R Greathouse IV, Sep 29 2011
|
|
|
CROSSREFS
| Cf. A055098. Identical to A043537 and A043562 for n<100.
Cf. A179239 [From Aaron Dunigan AtLee (aaron(AT)duniganatlee.com), Jul 14 2010]
Sequence in context: A043561 A043562 A043537 * A043563 A043538 A043564
Adjacent sequences: A047723 A047724 A047725 * A047727 A047728 A047729
|
|
|
KEYWORD
| nonn,easy,base,nice
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
|
|
|
EXTENSIONS
| Corrected by Henry Bottomley (se16(AT)btinternet.com), Apr 19 2000
|
| |
|
|
