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A152717
Triangle T(n,k) read by rows: T(n,k) = 5^min(k, n-k) = 5^A004197(n,k).
5
1, 1, 1, 1, 5, 1, 1, 5, 5, 1, 1, 5, 25, 5, 1, 1, 5, 25, 25, 5, 1, 1, 5, 25, 125, 25, 5, 1, 1, 5, 25, 125, 125, 25, 5, 1, 1, 5, 25, 125, 625, 125, 25, 5, 1, 1, 5, 25, 125, 625, 625, 125, 25, 5, 1, 1, 5, 25, 125, 625, 3125, 625, 125, 25, 5, 1
OFFSET
0,5
COMMENTS
Row sums are: {1, 2, 7, 12, 37, 62, 187, 312, 937, 1562, 4687,...}
FORMULA
T(n,k) = 5^min(k, n-k). - Philippe Deléham, Feb 25 2014
EXAMPLE
{1},
{1, 1},
{1, 5, 1},
{1, 5, 5, 1},
{1, 5, 25, 5, 1},
{1, 5, 25, 25, 5, 1},
{1, 5, 25, 125, 25, 5, 1},
{1, 5, 25, 125, 125, 25, 5, 1},
{1, 5, 25, 125, 625, 125, 25, 5, 1},
{1, 5, 25, 125, 625, 625, 125, 25, 5, 1},
{1, 5, 25, 125, 625, 3125, 625, 125, 25, 5, 1}
MATHEMATICA
Clear[a, k, m]; k = 5; a[0] = {1}; a[1] = {1, 1};
a[n_] := a[n] = Join[{1}, k*a[n - 2], {1}];
Table[a[n], {n, 0, 10}];
Flatten[%]
CROSSREFS
KEYWORD
nonn,easy,tabl
AUTHOR
EXTENSIONS
Better name from Philippe Deléham, Feb 25 2014
STATUS
approved