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A372890 Sum of binary ranks of all integer partitions of n, where the binary rank of a partition y is given by Sum_i 2^(y_i-1). 8

%I #15 May 24 2024 14:30:29

%S 0,1,4,10,25,52,115,228,471,931,1871,3687,7373,14572,29049,57694,

%T 115058,229101,457392,912469,1822945,3640998,7277426,14544436,

%U 29079423,58137188,116254386,232465342,464889800,929691662,1859302291,3718428513,7436694889,14873042016

%N Sum of binary ranks of all integer partitions of n, where the binary rank of a partition y is given by Sum_i 2^(y_i-1).

%H Alois P. Heinz, <a href="/A372890/b372890.txt">Table of n, a(n) for n = 0..3321</a>

%F From _Alois P. Heinz_, May 23 2024: (Start)

%F a(n) = Sum_{k=1..n} 2^(k-1) * A066633(n,k).

%F a(n) mod 2 = A365410(n-1) for n>=1. (End)

%e The partitions of 4 are (4), (3,1), (2,2), (2,1,1), (1,1,1,1), with respective binary ranks 8, 5, 4, 4, 4 with sum 25, so a(4) = 25.

%p b:= proc(n, i) option remember; `if`(n=0 or i=1, [1, n],

%p b(n, i-1)+(p->[0, p[1]*2^(i-1)]+p)(b(n-i, min(n-i, i))))

%p end:

%p a:= n-> b(n$2)[2]:

%p seq(a(n), n=0..33); # _Alois P. Heinz_, May 23 2024

%t Table[Total[Total[2^(#-1)]&/@IntegerPartitions[n]],{n,0,10}]

%Y For Heinz number (not binary rank) we have A145519, row sums of A215366.

%Y For Heinz number the strict version is A147655, row sums of A246867.

%Y The strict version is A372888, row sums of A118462.

%Y A005117 gives Heinz numbers of strict integer partitions.

%Y A048675 gives binary rank of prime indices, distinct A087207.

%Y A061395 gives greatest prime index, least A055396.

%Y A118457 lists strict partitions in Mathematica order.

%Y A277905 groups all positive integers by binary rank of prime indices.

%Y Binary indices (A048793):

%Y - length A000120, complement A023416

%Y - min A001511, opposite A000012

%Y - max A029837 or A070939, opposite A070940

%Y - sum A029931, product A096111

%Y - reverse A272020

%Y - complement A368494, sum A359400

%Y - opposite complement A371571, sum A359359

%Y - opposite A371572, sum A230877

%Y Cf. A000041, A005940, A018819, A019565, A066633, A225620, A344086, A365410.

%K nonn

%O 0,3

%A _Gus Wiseman_, May 23 2024

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Last modified September 18 06:58 EDT 2024. Contains 375996 sequences. (Running on oeis4.)