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A089290
Digital root of floor(Pi*10^n), Pi=3.14....
3
3, 4, 8, 9, 5, 5, 7, 4, 9, 3, 8, 7, 7, 5, 5, 8, 1, 4, 3, 7, 4, 6, 3, 7, 1, 4, 3, 6, 8, 6, 6, 2, 2, 4, 3, 2, 6, 7, 7, 5, 6, 3, 3, 6, 6, 6, 9, 7, 3, 4, 4, 9, 8, 1, 1, 1, 8, 3, 3, 7, 2, 7, 7, 9, 3, 3, 1, 9, 1, 7, 2, 2, 8, 1, 9, 6, 8, 8, 7, 7, 7, 6, 3, 5, 4, 4, 7
OFFSET
0,1
LINKS
FORMULA
a(n) = A010888(A011545(n)).
EXAMPLE
n=10: floor(Pi*10^n) = 31415926535 -> 3 + 1 + 4 + 1 + 5 + 9 + 2 + 6 + 5 + 3 + 5 = 44 -> 4 + 4 = 8, so a(10)=8.
MAPLE
A089290 := proc(n) Digits:=n+20: return ((floor(Pi*10^n)-1) mod 9) + 1: end: seq(A089290(n), n=0..100); # Nathaniel Johnston, May 04 2011
MATHEMATICA
Table[ Mod[ Floor[ Pi*10^n], 9], {n, 0, 104}] /. 0 -> 9 (* Robert G. Wilson v, Oct 31 2003 *)
CROSSREFS
Sequence in context: A125219 A075562 A316137 * A296497 A019811 A075746
KEYWORD
nonn,easy,base
AUTHOR
Reinhard Zumkeller, Oct 30 2003
EXTENSIONS
More terms from Ray Chandler and Robert G. Wilson v, Oct 31 2003
STATUS
approved