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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.

A351006 Number of integer partitions of n into parts that are alternately unequal and equal.

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%I A351006 #12 Feb 04 2022 07:44:09
%S A351006 1,1,1,2,3,4,4,6,7,9,10,12,14,16,18,22,25,28,31,36,40,46,50,56,64,71,
%T A351006 78,88,96,106,118,130,143,158,172,190,209,228,248,274,298,324,354,384,
%U A351006 418,458,494,536,584,631,683,742,800,864,936,1010,1088,1176,1264
%N A351006 Number of integer partitions of n into parts that are alternately unequal and equal.
%e A351006 The a(1) = 1 through a(11) = 12 partitions (A = 10, B = 11):
%e A351006   1  2  3   4    5    6    7    8     9      A      B
%e A351006         21  31   32   42   43   53    54     64     65
%e A351006             211  41   51   52   62    63     73     74
%e A351006                  311  411  61   71    72     82     83
%e A351006                            322  422   81     91     92
%e A351006                            511  611   522    433    A1
%e A351006                                 3221  711    622    533
%e A351006                                       4221   811    722
%e A351006                                       32211  5221   911
%e A351006                                              42211  4331
%e A351006                                                     6221
%e A351006                                                     52211
%t A351006 Table[Length[Select[IntegerPartitions[n],And@@Table[#[[i]]==#[[i+1]],{i,2,Length[#]-1,2}]&&And@@Table[#[[i]]!=#[[i+1]],{i,1,Length[#]-1,2}]&]],{n,0,30}]
%Y A351006 Without equalities we have A122129, opposite A122135, even-length A351008.
%Y A351006 The non-strict version is A351003, opposite A351004, even-length A351012.
%Y A351006 The alternately equal and unequal version is A351005, even-length A035457.
%Y A351006 The even-length case is A351007.
%Y A351006 Cf. A000070, A003242, A018819, A027383, A035363, A088218, A122134, A344605, A350842, A350844, A351011.
%K A351006 nonn
%O A351006 0,4
%A A351006 _Gus Wiseman_, Jan 31 2022