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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
2, 5, 10, 30, 130, 390, 2210, 6630, 46410, 192270, 1345890, 7113990, 49797930, 291673590, 2041715130 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

From Amiram Eldar, Jun 27 2020: (Start)

Indices of records of A086275.

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

LINKS

Table of n, a(n) for n=1..15.

MATHEMATICA

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

CROSSREFS

Cf. A001221, A001222 (integer factorizations).

Cf. A078458, A086275 (Gaussian factorizations).

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

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

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

Cf. A332476.

Sequence in context: A006404 A101957 A047113 * A239629 A155580 A226963

Adjacent sequences:  A239627 A239628 A239629 * A239631 A239632 A239633

KEYWORD

nonn,more

AUTHOR

T. D. Noe, Mar 31 2014

EXTENSIONS

a(13)-a(15) from Amiram Eldar, Jun 27 2020

STATUS

approved

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Last modified July 12 13:27 EDT 2020. Contains 335663 sequences. (Running on oeis4.)