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A236903
Row sums of an analog of Pascal's triangle resulting from replacing addition with concatenation in the construction rule.
1
1, 2, 13, 224, 113335, 2222244446, 11111333333333555557, 22222222222222444444444444446666668, 1111111111111133333333333333333333333333335555555555555555555577777779
OFFSET
0,2
COMMENTS
Number of digits of a(n) is A001405(n).
a(2n) begins with exactly A000108(n) 1's. - Vladimir Shevelev, Feb 07 2014
LINKS
EXAMPLE
Triangle begins
. 1
.
. 1 1
.
. 1 11 1
.
. 1 111 111 1
.
. 1 1111 111111 1111 1
MAPLE
a:= n-> add((10^binomial(n, k)-1)/9, k=0..n):
seq(a(n), n=0..8); # Alois P. Heinz, Feb 01 2014
CROSSREFS
Sequence in context: A069569 A255882 A015196 * A277452 A268703 A373871
KEYWORD
nonn,base
AUTHOR
Vladimir Shevelev, Feb 01 2014
STATUS
approved