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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

%I

%S 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,

%T 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,

%U 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

%N 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).

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

%e 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).

%Y Cf. A141809, A027748.

%K nonn,tabf

%O 1,2

%A _Leroy Quet_, Jul 07 2008

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Last modified January 18 03:13 EST 2019. Contains 319260 sequences. (Running on oeis4.)