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A113978 a(n)=Sum(d|n)(10^(n-d)). 0
1, 11, 101, 1101, 10001, 111001, 1000001, 11010001, 101000001, 1100100001, 10000000001, 111101000001, 1000000000001, 11000010000001, 101010000000001, 1101000100000001, 10000000000000001, 111001001000000001 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

A074854 in base 2. Stacking the elements gives the triangle A051731.

FORMULA

G.f.: Sum_{k>0} 10^(k-1)*x^k/(1-10^(k-1)*x^k).

PROG

(PARI) a(n)=if(n<1, 0, 10^n*polcoeff(sum(k=1, n, 10/(10-x^k), x*O(x^n)), n))

CROSSREFS

Sequence in context: A113999 A068166 A199306 * A193707 A006943 A073030

Adjacent sequences:  A113975 A113976 A113977 * A113979 A113980 A113981

KEYWORD

easy,nonn

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Nov 11 2005

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Last modified February 15 05:45 EST 2012. Contains 205694 sequences.