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A176809 Triangle read by rows: T(n,m) = 1 - (ceiling((n-1)/m) + ceiling((n-1)/(n-m+1))) + ceiling((n-1)/1) + ceiling((n-1)/(n-1+1)). 0
1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 3, 2, 3, 1, 1, 3, 3, 3, 3, 1, 1, 4, 4, 4, 4, 4, 1, 1, 4, 4, 5, 5, 4, 4, 1, 1, 5, 5, 6, 6, 6, 5, 5, 1, 1, 5, 6, 6, 7, 7, 6, 6, 5, 1, 1, 6, 6, 7, 8, 8, 8, 7, 6, 6, 1, 1, 6, 7, 8, 8, 9, 9, 8, 8, 7, 6, 1, 1, 7, 8, 9, 9, 10, 10, 10, 9, 9, 8, 7, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Row sums are {1, 2, 4, 6, 10, 14, 22, 28, 40, 50, ...}.

LINKS

Table of n, a(n) for n=1..91.

FORMULA

T(n,m) = 1 - (ceiling((n-1)/m) + ceiling((n-1)/(n-m+1))) + ceiling((n-1)/1) + ceiling((n-1)/(n-1+1)).

EXAMPLE

{1},

{1, 1},

{1, 2, 1},

{1, 2, 2, 1},

{1, 3, 2, 3, 1},

{1, 3, 3, 3, 3, 1},

{1, 4, 4, 4, 4, 4, 1},

{1, 4, 4, 5, 5, 4, 4, 1},

{1, 5, 5, 6, 6, 6, 5, 5, 1},

{1, 5, 6, 6, 7, 7, 6, 6, 5, 1}

MATHEMATICA

t[n_, m_] = 1 - (Ceiling[(n - 1)/m] + Ceiling[(n - 1)/(n - m + 1)]) + Ceiling[(n - 1)/1] + Ceiling[(n - 1)/(n - 1 + 1)];

Table[Table[t[n, m], {m, 1, n}], {n, 1, 10}];

Flatten[%]

CROSSREFS

Cf. A176298.

Sequence in context: A115514 A326038 A122632 * A317815 A318423 A318091

Adjacent sequences:  A176806 A176807 A176808 * A176810 A176811 A176812

KEYWORD

nonn,tabl

AUTHOR

Roger L. Bagula, Apr 26 2010

EXTENSIONS

Offset corrected by Alois P. Heinz, Jul 04 2019

STATUS

approved

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Last modified January 23 01:30 EST 2020. Contains 331166 sequences. (Running on oeis4.)