cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A159572 A triangular array related to ordered partitions and having row sums 1,2,5,14,43,144,523,2048,8597... A047970.

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%I A159572 #8 May 11 2014 05:17:11
%S A159572 1,1,1,1,3,1,1,6,5,2,1,10,14,12,6,1,15,30,39,39,20,1,21,55,95,138,142,
%T A159572 71,1,28,91,195,364,548,551,270,1,36,140,357,804,1564,2317,2278,1100
%N A159572 A triangular array related to ordered partitions and having row sums 1,2,5,14,43,144,523,2048,8597... A047970.
%C A159572 The first five diagonals are essentially A000012, A000217, A000330, A086602 and A159571.
%C A159572 From _Alford Arnold_, Apr 20 2009: (Start)
%C A159572 After the first two diagonals, each additional diagonal is computed using blocks of source partitions (defined in A053445).
%C A159572 The size of each block increases by powers of two; e.g. 22, 33 222, 44 332 333 2222; etc.
%C A159572 Each source partition can be associated with a specific sequence as illustrated in the below example using partition 332: grow the leftmost value to form 432 then append "1" to form 3321. in like manner, generate 532 4321 and 33211 from the previously formed cases. Note that the number of arrangements are 3, 6+12, and 6+24+30 respectively and that we now have three terms of A006011: 3 18 and 60.
%C A159572 Next we note that 6 39 138 364 804 ... A159571 resulted from summing term by term, the sequences associated with partitions 44 332 333 and 2222:
%C A159572 1...5..14...30...55
%C A159572 3..18..60..150..315
%C A159572 1...7..25...65..140
%C A159572 1...9..39..119..294
%C A159572 (End)
%Y A159572 Cf. A047970 (row sums), A000012, A000217, A000330, A086602, A159571.
%Y A159572 Cf. A053445. - _Alford Arnold_, Apr 20 2009
%K A159572 nonn,tabl,obsc
%O A159572 1,5
%A A159572 _Alford Arnold_, Apr 16 2009
%E A159572 Submitted without a definition. - _N. J. A. Sloane_, Apr 18 2009
%E A159572 More terms from _Alford Arnold_, Oct 06 2009