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A174690 A symmetrical triangle sequence: t(n,m)=n!*Binomial[n, m] - n! + 1 0
1, 1, 1, 1, 3, 1, 1, 13, 13, 1, 1, 73, 121, 73, 1, 1, 481, 1081, 1081, 481, 1, 1, 3601, 10081, 13681, 10081, 3601, 1, 1, 30241, 100801, 171361, 171361, 100801, 30241, 1, 1, 282241, 1088641, 2217601, 2782081, 2217601, 1088641, 282241, 1, 1, 2903041 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Row sums are:

{1, 2, 5, 28, 269, 3126, 41047, 604808, 9959049, 182165770, 3675974411,...}.

LINKS

Table of n, a(n) for n=0..46.

FORMULA

t(n,m)=n!*Binomial[n, m] - n! + 1

EXAMPLE

{1},

{1, 1},

{1, 3, 1},

{1, 13, 13, 1},

{1, 73, 121, 73, 1},

{1, 481, 1081, 1081, 481, 1},

{1, 3601, 10081, 13681, 10081, 3601, 1},

{1, 30241, 100801, 171361, 171361, 100801, 30241, 1},

{1, 282241, 1088641, 2217601, 2782081, 2217601, 1088641, 282241, 1},

{1, 2903041, 12700801, 30119041, 45360001, 45360001, 30119041, 12700801, 2903041, 1},

{1, 32659201, 159667201, 431827201, 758419201, 910828801, 758419201, 431827201, 159667201, 32659201, 1}

MATHEMATICA

t[n_, m_] = n!*Binomial[n, m] - n! + 1;

Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}];

Flatten[%]

CROSSREFS

Sequence in context: A094573 A055154 A015112 * A156869 A153090 A203002

Adjacent sequences:  A174687 A174688 A174689 * A174691 A174692 A174693

KEYWORD

nonn,tabl,uned

AUTHOR

Roger L. Bagula, Mar 27 2010

STATUS

approved

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Last modified April 25 00:29 EDT 2019. Contains 322446 sequences. (Running on oeis4.)