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A179285
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Triangle T(n,k) read by rows, defined by: T(1,1)=1; n > 1 and k=1: T(n,1) = T(n-1,2) + T(n,2); k=2: T(n,2) = A000196(n-1); k > 2: T(n,k) = (Sum_{i=1..k-1} T(n-i,k-1)) - (Sum_{i=1..k-1} T(n-i,k)).
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2
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1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 3, 2, 0, 1, 1, 4, 2, 2, 0, 1, 1, 4, 2, 2, 1, 0, 1, 1, 4, 2, 0, 2, 1, 0, 1, 1, 4, 2, 2, 1, 1, 1, 0, 1, 1, 5, 3, 2, 0, 1, 1, 1, 0, 1, 1, 6, 3, 1, 1, 1, 0, 1, 1, 0, 1, 1, 6, 3, 3, 3, 0, 1, 0, 1, 1, 0, 1, 1, 6, 3, 2, 2, 2, 1, 0, 0, 1, 1, 0, 1, 1, 6, 3, 1, 0, 2, 1, 1, 0, 0, 1, 1, 0, 1, 1
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OFFSET
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1,4
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COMMENTS
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The second column, sequence A000196, is the initial condition for the recurrence in this triangle. See A051731, formula entered on Feb 16 2010 for the more pure form of this recurrence.
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LINKS
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FORMULA
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T(1,1)=1; n > 1 and k=1: T(n,1) = T(n-1,2) + T(n,2); k=2: T(n,2) = A000196(n-1); k > 2: T(n,k) = (Sum_{i=1..k-1} T(n-i,k-1)) - (Sum_{i=1..k-1} T(n-i,k)).
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EXAMPLE
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Triangle begins:
1;
1, 1;
2, 1, 1;
2, 1, 1, 1;
3, 2, 0, 1, 1;
4, 2, 2, 0, 1, 1;
4, 2, 2, 1, 0, 1, 1;
4, 2, 0, 2, 1, 0, 1, 1;
4, 2, 2, 1, 1, 1, 0, 1, 1;
5, 3, 2, 0, 1, 1, 1, 0, 1, 1;
6, 3, 1, 1, 1, 0, 1, 1, 0, 1, 1;
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PROG
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(Excel) Using European dot comma style:
=if(and(row()=1; column()=1); 1; if(row()>=column(); if(column()=1; indirect(address(row()-1; column()+1))+indirect(address(row(); column()+1)); if(column()=2; floor(((row()-1)^0, 5); 1); if(row()>=column(); sum(indirect(address(row()-column()+1; column()-1; 4)&":"&address(row()-1; column()-1; 4); 4))-sum(indirect(address(row()-column()+1; column(); 4)&":"&address(row()-1; column(); 4); 4)); 0))); 0))
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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