

A104169


Highly decomposable Smith numbers. A Smith number which sets a record for the number of prime factors (counting multiplicity) starting from first Smith number is called a highly decomposable Smith number.


1



4, 27, 378, 576, 2688, 17496, 44928, 75776, 168960, 319488, 958464, 2883584, 5767168, 7077888, 279969792, 544997376, 778567680, 2579496960, 3875536896, 22749904896, 60699967488, 87509958656, 164886478848
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OFFSET

1,1


COMMENTS

Except for 27, no other highly decomposable Smith number below 10^9 is odd. It is conjectured that except for 27, all highly decomposable Smith numbers are even.


REFERENCES

S. S. Gupta, Smith Numbers, Mathematical Spectrum, 37 (2004/5), 2729.


LINKS

Table of n, a(n) for n=1..23.
S. S. Gupta, Smith Numbers.


EXAMPLE

a(3) = 378 because the Smith number 378 has 5 prime factors which is > any Smith number < 378.


CROSSREFS

Cf. A006753, A104168.
Sequence in context: A320961 A239726 A058155 * A271615 A271616 A123672
Adjacent sequences: A104166 A104167 A104168 * A104170 A104171 A104172


KEYWORD

nonn,base,more,changed


AUTHOR

Shyam Sunder Gupta, Mar 10 2005 and May 03 2005


EXTENSIONS

a(20)a(23) from Donovan Johnson, Jan 02 2013


STATUS

approved



