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A348342 Noninfinitary highly composite numbers: where the number of noninfinitary divisors (A348341) increases to a record. 2

%I #12 Oct 15 2021 05:54:47

%S 1,4,12,16,36,48,144,240,576,720,1680,2880,3600,5040,11520,14400,

%T 15120,20160,25200,45360,55440,80640,100800,166320,176400,226800,

%U 277200,498960,720720,887040,1108800,1587600,1940400,2494800,3603600,6486480,9979200,11531520,14414400

%N Noninfinitary highly composite numbers: where the number of noninfinitary divisors (A348341) increases to a record.

%C The record numbers of noninfinitary divisors are 0, 1, 2, 3, 5, 6, 11, 12, 13, 22, 24, 26, 37, 44, 46, ... (see the link for more values).

%H Amiram Eldar, <a href="/A348342/b348342.txt">Table of n, a(n) for n = 1..468</a>

%H Amiram Eldar, <a href="/A348342/a348342.txt">Table of n, a(n), A348341(a(n)) for n = 1..468</a>

%t nid[1] = 0; nid[n_] := DivisorSigma[0, n] - Times @@ Flatten[2^DigitCount[#, 2, 1] & /@ FactorInteger[n][[;; , 2]]]; dm = -1; s = {}; Do[If[(d = nid[n]) > dm, dm = d; AppendTo[s, n]], {n, 1, 10^6}]; s

%Y Cf. A348341.

%Y Subsequence of A025487.

%Y Similar sequences: A002182, A002110 (unitary), A037992 (infinitary), A293185, A306736, A307845, A309141, A318278, A322484, A335386.

%K nonn

%O 1,2

%A _Amiram Eldar_, Oct 13 2021

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Last modified August 14 10:15 EDT 2024. Contains 375159 sequences. (Running on oeis4.)