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A142593
Irregular triangle read by rows: row n gives successive exponents in prime factorization of A141900(n).
4
1, 2, 1, 3, 1, 4, 1, 1, 5, 1, 1, 6, 1, 1, 1, 7, 1, 1, 1, 8, 3, 1, 1, 9, 3, 1, 1, 10, 3, 1, 1, 1, 11, 3, 1, 1, 1, 12, 3, 1, 1, 1, 1, 13, 3, 1, 1, 1, 1, 14, 3, 1, 1, 1, 1, 15, 3, 1, 1, 1, 1, 16, 3, 1, 1, 1, 1, 1, 17, 3, 1, 1, 1, 1, 1, 18, 3, 1, 1, 1, 1, 1, 1, 19, 3, 1, 1, 1, 1, 1, 1, 20, 3, 1, 1
OFFSET
1,2
LINKS
David Applegate, Maple program which generates this triangle [The command hpat(n); returns the n-th row in an encoded form.]
EXAMPLE
Triangle begins:
1
2 1
3 1
4 1 1
5 1 1
6 1 1 1
7 1 1 1
8 3 1 1
9 3 1 1
10 3 1 1 1
11 3 1 1 1
12 3 1 1 1 1
Row 8 = [8,3,1,1] because A141900(8) = 2^8*3^3*5*7 = 241920.
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
David Applegate, Tim Kunisky (tkunisky(AT)gmail.com), Gerry Manoim (gerrymanoim(AT)gmail.com) and N. J. A. Sloane, Sep 25 2008
STATUS
approved