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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
OFFSET
0,3
COMMENTS
a(2^n-1)=(-1)^n.
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: A395457 A373628 A138342 * A051380 A374504 A136238
KEYWORD
easy,sign
AUTHOR
Paul Barry, Dec 11 2004
STATUS
approved