|
| |
|
|
A076466
|
|
a(1)=1 a(n) = a(n-1) + ((-1)^a(n-1)*a(n-1)) mod n.
|
|
0
| |
|
|
1, 2, 4, 4, 8, 10, 13, 16, 23, 30, 38, 40, 41, 42, 54, 60, 69, 72, 87, 100, 116, 122, 129, 144, 163, 182, 202, 208, 213, 240, 263, 288, 312, 318, 321, 324, 352, 362, 373, 400, 431, 462, 494, 504, 513, 552, 587, 624, 660, 670, 677, 728, 767, 810, 850, 860, 865
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
FORMULA
| a(n) is asymptotic to 4n^2/15; a(n)=4n^2/15 if n is of the form 30*(2k+1) hence a(60k+30) = 1800*(2k+1)^2
|
|
|
EXAMPLE
| a(8) = a(7) + ( (-1)^a(7)*a(7)) mod 8 = 13 + (- 13) mod 8 = 13 + 3 = 16
|
|
|
MATHEMATICA
| RecurrenceTable[{a[1]==1, a[n]==a[n-1]+Mod[(-1)^a[n-1] a[n-1], n]}, a, {n, 60}] (* From Harvey P. Dale, Nov 09 2011 *)
|
|
|
PROG
| (PARI) a(n)=a(n-1)+((-1)^a(n-1)*a(n-1))%n
|
|
|
CROSSREFS
| Sequence in context: A188824 A181212 A029599 * A073117 A039879 A125204
Adjacent sequences: A076463 A076464 A076465 * A076467 A076468 A076469
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Benoit Cloitre (benoit7848c(AT)orange.fr), Nov 07 2002
|
| |
|
|
