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.

A330952 Number of integer partitions of n whose Heinz number (product of primes of parts) is divisible by all parts.

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%I A330952 #4 Jan 15 2020 22:48:30
%S A330952 1,1,1,2,2,3,5,6,8,11,14,20,25,32,42,54,69,87,109,137,172,215,269,331,
%T A330952 409,499,612,751,917,1111,1344,1626,1963,2359,2834,3396,4065,4849,
%U A330952 5779,6865,8146,9658,11424,13483,15898,18710,21999,25823,30272,35417,41397
%N A330952 Number of integer partitions of n whose Heinz number (product of primes of parts) is divisible by all parts.
%C A330952 The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). This gives a bijective correspondence between positive integers and integer partitions.
%e A330952 The a(1) = 1 through a(9) = 11 partitions:
%e A330952   1  11  21   211   221    321     2221     3221      621
%e A330952          111  1111  2111   411     3211     4211      3321
%e A330952                     11111  2211    4111     22211     22221
%e A330952                            21111   22111    32111     32211
%e A330952                            111111  211111   41111     42111
%e A330952                                    1111111  221111    222111
%e A330952                                             2111111   321111
%e A330952                                             11111111  411111
%e A330952                                                       2211111
%e A330952                                                       21111111
%e A330952                                                       111111111
%t A330952 Table[Length[Select[IntegerPartitions[n],And@@Table[Divisible[Times@@Prime/@#,i],{i,#}]&]],{n,0,30}]
%Y A330952 The Heinz numbers of these partitions are given by A120383.
%Y A330952 Partitions whose product is divisible by their sum are A057568.
%Y A330952 Partitions whose Heinz number is divisible by their product are A324925.
%Y A330952 Partitions whose Heinz number is divisible by their sum are A330950.
%Y A330952 Cf. A056239, A112798, A324756, A326149, A326155, A330953, A330954, A331383.
%K A330952 nonn
%O A330952 0,4
%A A330952 _Gus Wiseman_, Jan 15 2020