Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A003132
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A003132 Sum of squares of digits of n.
(Formerly M3355)
+0
29
0, 1, 4, 9, 16, 25, 36, 49, 64, 81, 1, 2, 5, 10, 17, 26, 37, 50, 65, 82, 4, 5, 8, 13, 20, 29, 40, 53, 68, 85, 9, 10, 13, 18, 25, 34, 45, 58, 73, 90, 16, 17, 20, 25, 32, 41, 52, 65, 80, 97, 25, 26, 29, 34, 41, 50, 61, 74, 89, 106, 36, 37, 40, 45, 52, 61, 72, 85, 100, 117, 49 (list; graph; listen)
OFFSET

0,3

COMMENT

It is easy to show that a(n) < 81*(log(n)+1) [log = base 10]. - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Mar 25 2006

REFERENCES

J.-P. Allouche and J. Shallit, The ring of k-regular sequences, II, Theoret. Computer Sci., 307 (2003), 3-29.

B. M. Stewart, Sums of functions of digits, Cand. J. Math., 12 (1960), 374-389.

LINKS

T. D. Noe, Table of n, a(n) for n=0..10000

J.-P. Allouche and J. Shallit, The Ring of k-regular Sequences, II

FORMULA

a(n)=n^2-20*n*floor(n/10)+81*sum{k>0,floor(n/10^k)^2}+20*sum{k>0,floor(n/10^k)*(floor(n/10^k)-floor(n/10^(k+1)))}. - Hieronymus Fischer (Hieronymus.Fischer(AT)gmx.de), Jun 17 2007

a(10n+k)=a(n)+k^2, 0<=k<10. - Hieronymus Fischer (Hieronymus.Fischer(AT)gmx.de), Jun 17 2007

MAPLE

for n from 0 to 6 do seq(n^2+j^2, j=0..9 ); od; - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Nov 06 2006

MATHEMATICA

Table[Sum[DigitCount[n][[i]]*i^2, {i, 1, 9}], {n, 1, 40}] - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Mar 25 2006

CROSSREFS

Cf. A052034, A052035.

Cf. A007953, A055017, A076313, A076314.

Adjacent sequences: A003129 A003130 A003131 this_sequence A003133 A003134 A003135

Sequence in context: A063462 A098736 A002015 this_sequence A062331 A069940 A118881

KEYWORD

nonn,easy,base,nice

AUTHOR

njas

EXTENSIONS

More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Mar 25 2006

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified October 10 20:39 EDT 2008. Contains 144831 sequences.


AT&T Labs Research