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A285807
Square array A(m,n) = concatenation of { m, m+1, ..., m+n }, with m, n >= 1, read by falling antidiagonals.
1
12, 123, 23, 1234, 234, 34, 12345, 2345, 345, 45, 123456, 23456, 3456, 456, 56, 1234567, 234567, 34567, 4567, 567, 67, 12345678, 2345678, 345678, 45678, 5678, 678, 78, 123456789, 23456789, 3456789, 456789, 56789, 6789, 789, 89, 12345678910, 2345678910, 345678910, 45678910, 5678910, 678910, 78910, 8910
OFFSET
1,1
COMMENTS
A column n = 0 would have A(m,0) = m. A row m = 0 would have A(0,n) = A(1,n-1) for all n > 0.
EXAMPLE
A(1,1) = 12, concatenation of 1 & 2.
A(1,2) = 123, concatenation of 1, 2 and 3.
A(2,1) = 23, concatenation of 2 & 3.
The table starts:
12 123 1234 12345 123456 1234567 12345678 ...
23 234 2345 23456 234567 2345678 23456789 ...
34 345 3456 34567 345678 3456789 345678910 ...
45 456 4567 45678 456789 45678910 4567891011 ...
56 567 5678 56789 5678910 567891011 56789101112 ...
67 678 6789 678910 67891011 6789101112 678910111213 ...
78 789 78910 7891011 789101112 78910111213 7891011121314 ...
89 8910 891011 89101112 8910111213 891011121314 89101112131415 ...
910 91011 9101112 910111213 91011121314 9101112131415 910111213141516 ...
(...)
PROG
(PARI) a(m, n)={for(i=m+1, m+n, m=m*10^#digits(i)+i); m}
CROSSREFS
Cf. A285806 for the base-2 variant.
Sequence in context: A113574 A255307 A199592 * A078189 A278982 A167208
KEYWORD
nonn,base,tabl
AUTHOR
M. F. Hasler, Apr 27 2017
STATUS
approved