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A304235 Colossally abundant numbers that are highly composite, but not superior highly composite. 5

%I #12 Dec 28 2020 17:50:51

%S 160626866400,9316358251200,288807105787200,2021649740510400,

%T 224403121196654400,9200527969062830400,395622702669701707200,

%U 1970992304700453905270400,35468006523084668025340848000,135483209545341953934626770390608000

%N Colossally abundant numbers that are highly composite, but not superior highly composite.

%C Numbers m in A004490 that are also in A002182 but not A002201.

%C Subset of A166981. Numbers in this sequence are in neither A224078 nor A304234.

%C There are 32 terms in this sequence.

%C The smallest term is 2^4 * 3^2 * 5 * A002110(9) or the product of k = {1,1,2,3,9} in A002110.

%C The largest term is 2^9 * 3^5 * 5^3 * 7^2 * 11 * 13 * 17 * 19 * 23 * A002110(66) or the product of A002110(k) with k = {1,1,1,1,2,2,3,4,9,66}, a 146 digit decimal number.

%H Michael De Vlieger, <a href="/A304235/b304235.txt">Table of n, a(n) for n = 1..32</a>

%H Michael De Vlieger, <a href="/A304235/a304235.txt">Colossally abundant m that are also highly composite but not superior highly composite</a>

%H Michael De Vlieger, <a href="/A304235/a304235.png">Color coded plot of m A002182 and A004394 at (x,y) where A301414(x) * A002110(y) = m</a>, terms in this sequence are colored dark red.

%H Michael De Vlieger, <a href="/A304235/a304235_1.png">Annotated plot of a(n)</a> for 1 <= n <= 32 at (x,y) = (a(n)/A002110(A001221(a(n)), A002110(A001221(a(n)))

%t (* First, download b-files at A002182, A002201, and A004490 *)

%t With[{s = Import["b004490.txt", "Data"][[All, -1]], t = Import["b002182.txt", "Data"][[All, -1]], u = Import["b002201.txt", "Data"][[All, -1]]}, Select[Intersection[s, t], FreeQ[u, #] &]]

%Y Cf. A002110, A002182, A002201, A004394, A004490, A166981, A224078, A304234.

%K nonn,fini

%O 1,1

%A _Michael De Vlieger_, May 08 2018

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Last modified April 19 17:39 EDT 2024. Contains 371797 sequences. (Running on oeis4.)