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A101678 A modular binomial transform of 10^n. 1
1, -1, 9, 1, 89, -99, 991, -1, 9909, -9899, 88991, 9999, 899911, -999901, 9999009, 1, 99990089, -99990099, 899910991, 99989999, 8899099911, -9898999901, 99089999009, -99999999, 990999990091, -989999990101, 8899999911009, 999999990001, 89999999100089, -99999999000099 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

a(2^n-1)=(-1)^n.

LINKS

Table of n, a(n) for n=0..29.

FORMULA

a(n)=sum{k=0..floor(n/2), (-1)^A010060(n-2k)*mod(binomial(n-k, k), 2)10^k}

CROSSREFS

Cf. A101679.

Sequence in context: A038291 A075504 A138342 * A051380 A136238 A113394

Adjacent sequences:  A101675 A101676 A101677 * A101679 A101680 A101681

KEYWORD

easy,sign

AUTHOR

Paul Barry, Dec 11 2004

STATUS

approved

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Last modified December 19 18:59 EST 2014. Contains 252239 sequences.