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A097659
a(n) = 1001^n.
3
1, 1001, 1002001, 1003003001, 1004006004001, 1005010010005001, 1006015020015006001, 1007021035035021007001, 1008028056070056028008001, 1009036084126126084036009001, 1010045120210252210120045010001
OFFSET
0,2
COMMENTS
694 is the smallest exponent e such that 1001^e begins with a digit greater than 1: A000030(a(694)) = 2, A000030(a(693)) = 1. - Reinhard Zumkeller, Nov 05 2010
a(n) gives the n-th row of Pascal's triangle (A007318) as long as all the binomial coefficients have at most three digits, otherwise the binomial coefficients with more than three digits overlap. - Daniel Forgues, Aug 12 2012
REFERENCES
Rozsa Peter, Playing with Infinity, New York, Dover Publications, 1957.
FORMULA
From Philippe Deléham, Nov 30 2008: (Start)
a(n) = 1001*a(n-1), n > 0; a(0)=1.
G.f.: 1/(1-1001*x). (End)
PROG
(PARI) 1001^n \\ Charles R Greathouse IV, Jan 30 2012
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Reinhard Zumkeller, Aug 18 2004
STATUS
approved