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Search: id:A089225
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| A089225 |
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Triangle T(n,k) read by rows, defined by T(n,k) = (n-k)*T(n-1,k)+Sum(k=1..n, T(n-1,k)); T(1,1) = 1, T(1,k)= 0 if k >1. |
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+0
1
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| 1, 2, 1, 7, 4, 3, 35, 22, 17, 14, 228, 154, 122, 102, 88, 1834, 1310, 1060, 898, 782, 694, 17582, 13128, 10818, 9272, 8142, 7272, 6578, 195866, 151560, 126882, 109880, 97218, 87336, 79370, 72792, 2487832, 1981824, 1682196, 1470304, 1309776
(list; table; graph; listen)
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OFFSET
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1,2
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COMMENT
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Let M be the n X n matrix with M(i,i)=i, other entries 1. Then T(n,k) = permanent of n-1 X n-1 matrix obtained by omitting row k and column k from M.
T(n,1) = A003713(n). n-th row sum = T(n+1,n+1) = A007840(n). {1}, {2, 1}, {7, 4, 3}, {35, 22, 17, 14}, ...
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EXAMPLE
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n=4: M = |1,1,1,1|1, 2,1, 1|1, 1, 3, 1|1, 1, 1, 4|
T(4, 1) = permanent of |2, 1, 1|1, 3, 1|1, 1, 4| = 26+5+4 = 35
T(4, 2) = permanent of |1, 1, 1|1, 3, 1|1, 1, 4| = 13+5+4 = 22
T(4, 3) = permanent of |1, 1, 1|1, 2, 1|1, 1, 4| = 9+5+3 = 17
T(4, 4) = permanent of |1, 1, 1|1, 2, 1|1, 1, 3| = 7+4+3 = 14
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CROSSREFS
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Sequence in context: A122843 A167196 A107865 this_sequence A075085 A124048 A087059
Adjacent sequences: A089222 A089223 A089224 this_sequence A089226 A089227 A089228
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KEYWORD
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easy,nonn,tabl
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AUTHOR
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DELEHAM Philippe (kolotoko(AT)wanadoo.fr), Dec 10 2003
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