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A141810 Irregular table: Row n (of A001221(n) terms, for n>=2) consists of the largest powers that divides n of each distinct prime that divides n. Terms are arranged by the sizes of the prime-powers. Row 1 = (1). 4
1, 2, 3, 4, 5, 2, 3, 7, 8, 9, 2, 5, 11, 3, 4, 13, 2, 7, 3, 5, 16, 17, 2, 9, 19, 4, 5, 3, 7, 2, 11, 23, 3, 8, 25, 2, 13, 27, 4, 7, 29, 2, 3, 5, 31, 32, 3, 11, 2, 17, 5, 7, 4, 9, 37, 2, 19, 3, 13, 5, 8, 41, 2, 3, 7, 43, 4, 11, 5, 9, 2, 23, 47, 3, 16, 49, 2, 25, 3, 17, 4, 13, 53, 2, 27, 5, 11, 7, 8, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

In other words, except for row 1, row n contains the unitary prime power divisors of n. - Franklin T. Adams-Watters, May 05 2011

LINKS

Table of n, a(n) for n=1..90.

EXAMPLE

60 has the prime factorization of 2^2 * 3^1 * 5^1. So row 60 is, arranged by the sizes of the prime-powers, (3,4,5).

CROSSREFS

Cf. A141809, A027748.

Sequence in context: A215089 A161768 A213925 * A141809 A059711 A043265

Adjacent sequences:  A141807 A141808 A141809 * A141811 A141812 A141813

KEYWORD

nonn,tabf

AUTHOR

Leroy Quet, Jul 07 2008

STATUS

approved

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Last modified December 11 05:41 EST 2017. Contains 295868 sequences.