|
| |
|
|
A076160
|
|
Sod_4 - sod_3 + sod_2 - sod_1, where sod_k is the sum of k-th powers of digits of n.
|
|
0
|
|
|
|
0, 0, 10, 60, 204, 520, 1110, 2100, 3640, 5904, 0, 0, 10, 60, 204, 520, 1110, 2100, 3640, 5904, 10, 10, 20, 70, 214, 530, 1120, 2110, 3650, 5914, 60, 60, 70, 120, 264, 580, 1170, 2160, 3700, 5964, 204, 204, 214, 264, 408, 724, 1314, 2304, 3844, 6108
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
0,3
|
|
|
COMMENTS
|
A quasiperiodic function.
|
|
|
LINKS
|
Table of n, a(n) for n=0..49.
|
|
|
FORMULA
|
Sod_4 - sod_3 + sod_2 - sod_1 = sum(d(d-1)(d^2+1)), d's are digits of n
|
|
|
EXAMPLE
|
a(4) = 204 = 4(4-1)(4^2+1), a(5) = 520 = 5(5-1)(5^2+1).
|
|
|
MATHEMATICA
|
sod[n_]:=Module[{idn=IntegerDigits[n]}, Total[Total/@{-idn+idn^2-idn^3+idn^4}]]; Array[sod, 50, 0] (* From Harvey P. Dale, Sep 20 2011 *)
|
|
|
CROSSREFS
|
Sequence in context: A065641 A121874 A144560 * A004406 A003472 A112502
Adjacent sequences: A076157 A076158 A076159 * A076161 A076162 A076163
|
|
|
KEYWORD
|
nonn,base
|
|
|
AUTHOR
|
Zak Seidov, Nov 01 2002
|
|
|
STATUS
|
approved
|
| |
|
|
