

A064364


Positive integers sorted by A001414(n), the sum of their prime divisors, as the major key and n as the minor key.


7



1, 2, 3, 4, 5, 6, 8, 9, 7, 10, 12, 15, 16, 18, 14, 20, 24, 27, 21, 25, 30, 32, 36, 11, 28, 40, 45, 48, 54, 35, 42, 50, 60, 64, 72, 81, 13, 22, 56, 63, 75, 80, 90, 96, 108, 33, 49, 70, 84, 100, 120, 128, 135, 144, 162, 26, 44, 105, 112, 125, 126, 150, 160, 180, 192, 216, 243
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OFFSET

1,2


COMMENTS

This is a permutation of the positive integers.
a(1) could be taken as 0 because 1 is not a member of A001414 and one could start with a(0)=1 (see the W. Lang link).
The row length sequence of this array is A000607(n), n>=2.
If the array is [1,0,2,3,4,5,6,6,...] with offset 0 then the row length sequence is A000607(n), n>=0.


LINKS

Reinhard Zumkeller and Alois P. Heinz, Rows n = 1..60, flattened (first 32 rows from Reinhard Zumkeller)
W. Lang: First 16 rows.
H. Havermann: The first 100 sums (complete, a 6 MB file).
H. Havermann: Tables of sumofprimefactors sequences (overview with links to the first 50000 sums).
Index entries for sequences that are permutations of the natural numbers


EXAMPLE

The triangle reads:
1,
(0,) (see comment in link to "first 16 rows" by W. Lang)
2,
3,
4,
5, 6,
8, 9,
7, 10, 12,
15, 16, 18,
14, 20, 24, 27,
21, 25, 30, 32, 36,
11, 28, 40, 45, 48, 54,
35, 42, 50, 60, 64, 72, 81,
13, 22, 56, 63, 75, 80, 90, 96, 108,
...


PROG

(Haskell)
import Data.List (partition, union)
a064364 n k = a064364_tabf !! (n1) !! (k1)
a064364_row n = a064364_tabf !! (n1)
a064364_tabf = [1] : tail (f 1 [] 1 (map a000792 [2..])) where
f k pqs v (w:ws) = (map snd pqs') :
f (k + 1) (union pqs'' (zip (map a001414 us) us )) w ws where
us = [v + 1 .. w]
(pqs', pqs'') = partition ((== k) . fst) pqs
a064364_list = concat a064364_tabf
 Reinhard Zumkeller, Jun 11 2015


CROSSREFS

Cf. A001414.
Cf. A000607 (row lengths), A002098 (row sums), A056240 (least = first term in the nth row), A000792 (greatest term in the nth row).
Cf. A257815 (inverse).
Sequence in context: A097502 A265568 A265552 * A269855 A209274 A195184
Adjacent sequences: A064361 A064362 A064363 * A064365 A064366 A064367


KEYWORD

easy,nonn,tabf


AUTHOR

Howard A. Landman, Sep 25 2001


EXTENSIONS

More terms from Vladeta Jovovic, Sep 27 2005


STATUS

approved



