login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A055640 Number of nonzero digits in decimal expansion of n. 39
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,12

COMMENTS

Comment from Antti Karttunen, Sep 05 2004: (start)

Also number of characters needed to write the number n in classical Greek alphabetic system, up to n=999. The Greek alphabetic system assigned values to the letters as follows:

alpha = 1, beta = 2, gamma = 3, delta = 4, epsilon = 5, digamma = 6, zeta = 7, eta = 8, theta = 9, iota = 10, kappa = 20, lambda = 30, mu = 40, nu = 50, xi = 60, omicron = 70, pi = 80, koppa = 90, rho = 100, sigma = 200, tau = 300, upsilon = 400, phi = 500, chi = 600, psi = 700, omega = 800, sampi = 900. (end)

Partial sums see A102685. - Hieronymus Fischer, Jun 06 2012

REFERENCES

L. Threatte, The Greek Alphabet, in The World's Writing Systems, edited by Peter T. Daniels and William Bright, Oxford Univ. Press, 1996. p. 278.

LINKS

Hieronymus Fischer, Table of n, a(n) for n = 0..10000

Unicode Consortium, Unicode Home Page (Follow the link "Display Problems?" to find an appropriate information/font file to show the Greek characters correctly. Or look at the html-source to see their names).

FORMULA

From Hieronymus Fischer, Jun 06 2012: (Start)

a(n) = sum_{j=1..m+1} (floor(n/10^j+0.9) - floor(n/10^j)), where m = floor(log_10(n)).

a(n) = m + 1 - A055641(n).

G.f.: (1/(1-x))*Sum_{j>=0} (x^10^j - x^(10*10^j))/(1-x^10^(j+1)). (End)

a(n) = A055642(n) - A055641(n).

EXAMPLE

E.g. 129 is written as rho kappa theta in the old Greek system.

MATHEMATICA

Table[Count[IntegerDigits[n], _?(#>0&)], {n, 0, 120}] (* Harvey P. Dale, Mar 11 2012 *)

PROG

(Haskell)

a055640 n = length $ filter (/= '0') $ show n

-- Reinhard Zumkeller, May 02 2011

(PARI) a(n)=my(v=digits(n)); sum(i=1, #v, !!v[i]) \\ Charles R Greathouse IV, Aug 05 2012

CROSSREFS

Cf. A102669-A102685, A004719, A011540, A052382, A061745, A054899, A055641, A055642, A122840, A160093, A160094, A193238, A196563, A195564, A000120, A000788, A023416, A059015 (for base 2).

Differs from A098378 for the first time at position n=200 with a(200)=1, as only one nonzero arabic digit (and only one Greek letter) is needed for two hundred, while A098378(200)=2 as two characters are needed in the Ethiopic system.

Sequence in context: A297036 A231072 * A098378 A160093 A259143 A035931

Adjacent sequences:  A055637 A055638 A055639 * A055641 A055642 A055643

KEYWORD

nonn,base,easy,nice

AUTHOR

Henry Bottomley, Jun 06 2000

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 15 07:26 EDT 2018. Contains 313756 sequences. (Running on oeis4.)