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A239630 Factored over the Gaussian integers, the least number having n prime factors, excluding units 1, -1, i, and -i. 2

%I #9 Jun 27 2020 04:32:06

%S 2,5,10,30,130,390,2210,6630,46410,192270,1345890,7113990,49797930,

%T 291673590,2041715130

%N Factored over the Gaussian integers, the least number having n prime factors, excluding units 1, -1, i, and -i.

%C From _Amiram Eldar_, Jun 27 2020: (Start)

%C Indices of records of A086275.

%C Also, numbers with a record number of unitary divisors in Gaussian integers (A332476). (End)

%t nn = 12; t = Table[0, {nn}]; n = 0; found = 0; While[found < nn, n++; f = FactorInteger[n, GaussianIntegers -> True]; cnt = Length[f]; If[MemberQ[{-1, I, -I}, f[[1, 1]]], cnt--]; If[cnt <= nn && t[[cnt]] == 0, t[[cnt]] = n; found++]]; t

%Y Cf. A001221, A001222 (integer factorizations).

%Y Cf. A078458, A086275 (Gaussian factorizations).

%Y Cf. A239627 (number of Gaussian factors of n, including units).

%Y Cf. A239628 (similar to this sequence, but count all prime factors).

%Y Cf. A239629 (number of distinct factors, including units).

%Y Cf. A332476.

%K nonn,more

%O 1,1

%A _T. D. Noe_, Mar 31 2014

%E a(13)-a(15) from _Amiram Eldar_, Jun 27 2020

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Last modified April 18 08:27 EDT 2024. Contains 371769 sequences. (Running on oeis4.)