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A133081
An interpolation operator, companion to A133080.
3
1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1
OFFSET
1,1
COMMENTS
A133081 * [1,2,3,...] = A133090: (1, 1, 5, 3, 9, 5, 13, 7, 17, ...).
A133080: diagonal and subdiagonal are switched.
FORMULA
Infinite lower triangular matrix, (1,0,1,0,...) in the main diagonal and (1,1,1,...) in the subdiagonal.
EXAMPLE
First few rows of the triangle:
1;
1, 0;
0, 1, 1;
0, 0, 1, 0;
0, 0, 0, 1, 1;
...
PROG
(PARI) row(n) = vector(n, k, if (k==n-1, 1, if (k==n, n%2)));
lista(nn) = my(list=List()); for (n=1, nn, my(v=row(n)); for (k=1, #v, listput(list, v[k]))); Vec(list); \\ Michel Marcus, Mar 06 2022
CROSSREFS
Cf. A133080, A133090, A040001 (row sums).
Sequence in context: A191747 A330323 A280933 * A352573 A285345 A125999
KEYWORD
nonn,easy,tabl
AUTHOR
Gary W. Adamson, Sep 09 2007
EXTENSIONS
More terms from Michel Marcus, Mar 06 2022
STATUS
approved