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A176505
Triangle T(n,m) read by rows: T(n,m) = a(n) - a(m) - a(n-m) + 1, where a(n) = A000931(n+4).
1
1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 2, 2, 2, 1, 1, 1, 1, 2, 3, 2, 3, 2, 1, 1, 1, 2, 3, 4, 4, 4, 4, 3, 2, 1, 1, 2, 4, 5, 5, 6, 5, 5, 4, 2, 1
OFFSET
0,25
LINKS
FORMULA
T(n,m) = a(n) - a(m) - a(n-m) + 1, a(n) = A000931(n+4).
EXAMPLE
Triangle:
{1},
{1, 1},
{1, 0, 1},
{1, 0, 0, 1},
{1, 1, 1, 1, 1},
{1, 0, 1, 1, 0, 1},
{1, 1, 1, 2, 1, 1, 1},
{1, 1, 2, 2, 2, 2, 1, 1},
{1, 1, 2, 3, 2, 3, 2, 1, 1},
{1, 2, 3, 4, 4, 4, 4, 3, 2, 1},
{1, 2, 4, 5, 5, 6, 5, 5, 4, 2, 1},
...
T(6,3) = a(6) - a(3) - a(6-3) + 1 = a(6) - 2 * a(3) + 1 = 3 - (2 * 1) + 1 = 2. - Indranil Ghosh, Feb 17 2017
MATHEMATICA
a[0] := 0; a[1] := 1; a[2] := 1;
a[n_] := a[n] = a[n - 2] + a[n - 3];
t[n_, m_] := t[n, m] = a[n] - a[m] - a[n - m] + 1;
Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}];
Flatten[%]
CROSSREFS
Cf. A000931.
Sequence in context: A184167 A352085 A036541 * A338521 A036225 A236859
KEYWORD
nonn,tabl,easy,less
AUTHOR
Roger L. Bagula, Apr 19 2010
EXTENSIONS
Name and formula sections corrected by Indranil Ghosh, Feb 17 2017
STATUS
approved