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A239629 Factored over the Gaussian integers, the least positive number having n prime factors, including units -1, i, and -i. 2
1, 2, 5, 10, 30, 130, 390, 2730, 13260, 64090, 192270, 1345890, 7113990, 49797930, 291673590, 2041715130 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Here -1, i, and -i are counted as factors. The factor 1 is counted only in a(1).
Indices of records of A239627. - Amiram Eldar, Jun 27 2020
LINKS
MATHEMATICA
nn = 12; t = Table[0, {nn}]; n = 0; found = 0; While[found < nn, n++; cnt = Length[FactorInteger[n, GaussianIntegers -> True]]; 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. A239630 (number of distinct factors, excluding units).
Sequence in context: A101957 A047113 A239630 * A155580 A226963 A018386
KEYWORD
nonn,more
AUTHOR
T. D. Noe, Mar 31 2014
EXTENSIONS
a(14)-a(16) from Amiram Eldar, Jun 27 2020
STATUS
approved

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Last modified March 29 09:44 EDT 2024. Contains 371268 sequences. (Running on oeis4.)