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Irregular triangle read by rows where T(n,k) is the number of integer partitions y of n such that Sum_i prime(y_i) = n + k.
8

%I #6 Jan 17 2020 17:41:25

%S 1,0,1,0,1,1,0,0,2,1,0,0,1,3,1,0,0,0,2,3,1,1,0,0,0,1,4,3,1,2,0,0,0,0,

%T 2,5,3,2,2,0,1,0,0,0,0,1,4,6,3,4,2,0,2,0,0,0,0,0,2,6,6,4,6,2,1,2,0,1,

%U 0,0,0,0,0,1,4,8,6,6,7,2,4,2,0,1,0,0,0,1

%N Irregular triangle read by rows where T(n,k) is the number of integer partitions y of n such that Sum_i prime(y_i) = n + k.

%e Triangle begins:

%e 1

%e 0 1

%e 0 1 1

%e 0 0 2 1

%e 0 0 1 3 1

%e 0 0 0 2 3 1 1

%e 0 0 0 1 4 3 1 2

%e 0 0 0 0 2 5 3 2 2 0 1

%e 0 0 0 0 1 4 6 3 4 2 0 2

%e 0 0 0 0 0 2 6 6 4 6 2 1 2 0 1

%e 0 0 0 0 0 1 4 8 6 6 7 2 4 2 0 1 0 0 0 1

%e 0 0 0 0 0 0 2 6 9 7 9 7 3 7 2 1 1 0 0 0 2

%e Row n = 8 counts the following partitions (empty column not shown):

%e (2222) (332) (44) (41111) (53) (611) (8)

%e (422) (431) (311111) (62) (5111) (71)

%e (3221) (3311) (2111111) (521)

%e (22211) (4211) (11111111)

%e (32111)

%e (221111)

%e Column k = 5 counts the following partitions:

%e (11111) (411) (43) (332) (3222) (22222)

%e (3111) (331) (422) (22221)

%e (21111) (421) (3221)

%e (3211) (22211)

%e (22111)

%t Table[Length[Select[IntegerPartitions[n],Total[Prime/@#]==m&]],{n,0,10},{m,n,Max@@Table[Total[Prime/@y],{y,IntegerPartitions[n]}]}]

%Y Row lengths are A331418.

%Y Row sums are A000041.

%Y Column sums are A331387.

%Y Shifting row n to the right n times gives A331416.

%Y Partitions whose sum of primes is divisible by their sum are A331379.

%Y Partitions whose product divides their sum of primes are A331381.

%Y Partitions whose product equals their sum of primes are A331383.

%Y Cf. A000040, A001414, A014689, A056239, A330950, A330953, A330954, A331378, A331415.

%K nonn,tabf

%O 0,9

%A _Gus Wiseman_, Jan 17 2020