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A340929 Heinz numbers of integer partitions of odd negative rank.

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%I A340929 #7 Jan 30 2021 22:51:47
%S A340929 4,12,16,18,27,40,48,60,64,72,90,100,108,112,135,150,160,162,168,192,
%T A340929 225,240,243,250,252,256,280,288,352,360,375,378,392,400,420,432,448,
%U A340929 528,540,567,588,600,625,630,640,648,672,700,768,792,810,832,880,882
%N A340929 Heinz numbers of integer partitions of odd negative rank.
%C A340929 The Heinz number of a partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k), giving a bijective correspondence between positive integers and integer partitions.
%C A340929 The Dyson rank of a nonempty partition is its maximum part minus its length. The rank of an empty partition is undefined.
%H A340929 Freeman J. Dyson, <a href="https://doi.org/10.1016/S0021-9800(69)80006-2">A new symmetry of partitions</a>, Journal of Combinatorial Theory 7.1 (1969): 56-61.
%H A340929 FindStat, <a href="http://www.findstat.org/StatisticsDatabase/St000145">St000145: The Dyson rank of a partition</a>
%F A340929 For all terms, A061395(a(n)) - A001222(a(n)) is odd and negative.
%e A340929 The sequence of partitions together with their Heinz numbers begins:
%e A340929        4: (1,1)             150: (3,3,2,1)
%e A340929       12: (2,1,1)           160: (3,1,1,1,1,1)
%e A340929       16: (1,1,1,1)         162: (2,2,2,2,1)
%e A340929       18: (2,2,1)           168: (4,2,1,1,1)
%e A340929       27: (2,2,2)           192: (2,1,1,1,1,1,1)
%e A340929       40: (3,1,1,1)         225: (3,3,2,2)
%e A340929       48: (2,1,1,1,1)       240: (3,2,1,1,1,1)
%e A340929       60: (3,2,1,1)         243: (2,2,2,2,2)
%e A340929       64: (1,1,1,1,1,1)     250: (3,3,3,1)
%e A340929       72: (2,2,1,1,1)       252: (4,2,2,1,1)
%e A340929       90: (3,2,2,1)         256: (1,1,1,1,1,1,1,1)
%e A340929      100: (3,3,1,1)         280: (4,3,1,1,1)
%e A340929      108: (2,2,2,1,1)       288: (2,2,1,1,1,1,1)
%e A340929      112: (4,1,1,1,1)       352: (5,1,1,1,1,1)
%e A340929      135: (3,2,2,2)         360: (3,2,2,1,1,1)
%t A340929 rk[n_]:=PrimePi[FactorInteger[n][[-1,1]]]-PrimeOmega[n];
%t A340929 Select[Range[2,100],OddQ[rk[#]]&&rk[#]<0&]
%Y A340929 Note: A-numbers of Heinz-number sequences are in parentheses below.
%Y A340929 These partitions are counted by A101707.
%Y A340929 The positive version is A101707 (A340604).
%Y A340929 The even version is A101708 (A340930).
%Y A340929 The not necessarily odd version is A064173 (A340788).
%Y A340929 A001222 counts prime factors.
%Y A340929 A027193 counts partitions of odd length (A026424).
%Y A340929 A047993 counts balanced partitions (A106529).
%Y A340929 A058695 counts partitions of odd numbers (A300063).
%Y A340929 A061395 selects the maximum prime index.
%Y A340929 A063995/A105806 count partitions by Dyson rank.
%Y A340929 A072233 counts partitions by sum and length.
%Y A340929 A112798 lists the prime indices of each positive integer.
%Y A340929 A168659 counts partitions whose length is divisible by maximum.
%Y A340929 A200750 counts partitions whose length and maximum are relatively prime.
%Y A340929 - Rank -
%Y A340929 A064174 counts partitions of nonnegative/nonpositive rank (A324562/A324521).
%Y A340929 A101198 counts partitions of rank 1 (A325233).
%Y A340929 A257541 gives the rank of the partition with Heinz number n.
%Y A340929 A324516 counts partitions with rank equal to maximum minus minimum part (A324515).
%Y A340929 A324518 counts partitions with rank equal to greatest part (A324517).
%Y A340929 A324520 counts partitions with rank equal to least part (A324519).
%Y A340929 A340601 counts partitions of even rank (A340602).
%Y A340929 A340692 counts partitions of odd rank (A340603).
%Y A340929 Cf. A003114, A056239, A096401, A117193, A117409, A325134, A326845, A340604, A340605, A340787, A340854/A340855.
%K A340929 nonn
%O A340929 1,1
%A A340929 _Gus Wiseman_, Jan 29 2021