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A133411
Smallest highly composite number of the form k*a(n-1) where k is an integer greater than 1.
5
1, 2, 4, 12, 24, 48, 240, 720, 5040, 10080, 20160, 221760, 665280, 8648640, 17297280, 294053760, 5587021440, 27935107200, 642507465600, 1927522396800, 13492656777600, 26985313555200, 782574093100800, 24259796886124800
OFFSET
1,2
COMMENTS
Conjecture: subsequence of A019505.
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..223 (computed from the 10000 term b-file of A002182 prepared from Flammenkamp's data)
EXAMPLE
6 is not in the sequence because 6 is not a multiple of 4, the previous term.
PROG
(PARI)
sublist_of_first_proper_multiple_terms_of(v) = { my(u=v[1], lista=List(u)); for(i=2, #v, if((v[i]>u)&&!(v[i]%u), u = v[i]; listput(lista, u))); Vec(lista); };
v133411 = sublist_of_first_proper_multiple_terms_of(v002182); \\ v002182 contains the terms of A002182.
A133411(n) = v133411[n]; \\ Antti Karttunen, Jan 10 2020
CROSSREFS
Cf. A002182, A019505, A328521, A330744 (primorial deflation).
Sequence in context: A348092 A343458 A328521 * A201078 A004645 A045687
KEYWORD
nonn
AUTHOR
J. Lowell, Nov 25 2007
EXTENSIONS
a(12)-a(24) from Donovan Johnson, Sep 09 2008
STATUS
approved