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Rewrite A087980(n) = Product_{i=1..m} p(i)^e(i) instead as Sum_{i=1..m} 2^(i-1), where m = omega(A087980(n)) = A001221(A087980(n)).
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%I #6 Jun 11 2023 12:29:33

%S 0,1,2,4,3,8,5,16,9,32,6,17,64,10,33,128,18,7,65,12,256,34,11,129,20,

%T 512,66,19,257,36,1024,13,130,24,35,513,68,2048,21,258,40,67,1025,132,

%U 4096,37,514,72,14,131,2049,25,260,48,8192,69,1026,136,22,259,4097,41,516,80,16384,133,2050,264,38

%N Rewrite A087980(n) = Product_{i=1..m} p(i)^e(i) instead as Sum_{i=1..m} 2^(i-1), where m = omega(A087980(n)) = A001221(A087980(n)).

%C Permutation of nonnegative numbers.

%C Rewriting nonnegative numbers n = Sum_{i=1..A000120(n)} 2^i instead as Product_{i=1..A000120(n)} p(i)^(e(i)+1) gives A362227.

%H Michael De Vlieger, <a href="/A363537/b363537.txt">Table of n, a(n) for n = 1..11157</a> (a(11157) = 2^64.)

%H Michael De Vlieger, <a href="/A363537/a363537.png">Log log scatterplot of a(n)</a>, n = 1..1203278.

%H Michael De Vlieger, <a href="/A363537/a363537_1.png">Plot S(n,k) in row a(n) of A272011 at (x,y) = (n,k)</a>, n = 1..2048.

%F a(2^k) = 2^(k-1) for k > 0.

%F a(A006939(k)) = 2^k-1 for k > 0.

%e Table relating this sequence to A087980, where b(n) = A087980(n), f(n) = A067255(n), g(n) = A272011(n), and a(n)_2 the binary expansion of a(n):

%e n b(n) f(b(n)) a(n) g(a(n)) a(n)_2

%e 1 1 0 0

%e 2 2 1 1 0 1

%e 3 4 2 2 1 1.

%e 4 8 3 4 2 1..

%e 5 12 2,1 3 1,0 11

%e 6 16 4 8 3 1...

%e 7 24 3,1 5 2,0 1.1

%e 8 32 5 16 4 1....

%e 9 48 4,1 9 3,0 1..1

%e 10 64 6 32 5 1.....

%e 11 72 3,2 6 2,1 11.

%e 12 96 5,1 17 4,0 1...1

%e 13 128 7 64 6 1......

%e 14 144 4,2 10 3,1 1.1.

%e 15 192 6,1 33 5,0 1....1

%e 16 256 8 128 7 1.......

%e 17 288 5,2 18 4,1 1..1.

%e 18 360 3,2,1 7 2,1,0 111

%e ...

%t m = 15; f[n_] := Times @@ MapIndexed[Prime[First[#2]]^(#1 + 1) &, Length[#] - Position[#, 1][[All, 1]]] &[IntegerDigits[n, 2]]; SortBy[Select[Array[{#, f[#]} &, 2^(m + 1)], Last[#] <= 2^m &], Last][[All, 1]]

%Y Cf. A000079, A001221, A006939, A087980, A362227.

%K nonn

%O 1,3

%A _Michael De Vlieger_, Jun 09 2023