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A233819 Least odd integer of each prime signature ordered by prime signatures occurrence. 2
1, 3, 9, 15, 27, 45, 81, 135, 105, 243, 225, 405, 315, 729, 675, 1215, 945, 2187, 2025, 1575, 3645, 1155, 3375, 2835, 6561, 6075, 4725, 10935, 3465, 10125, 8505, 19683, 18225, 14175, 32805, 10395, 30375, 11025, 25515, 59049, 23625, 54675, 17325, 50625, 42525, 98415, 31185, 91125, 33075, 76545, 177147, 70875 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) is the least odd integer with the same prime signature of A025487(n).

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

Will Nicholes, Prime Signatures

FORMULA

a(n) = A003961(A025487(n)). - Amiram Eldar, Jun 23 2019

EXAMPLE

a(7) is the first odd integer with prime signature {1,3} = 3^3*5 = 135

a(8) is the first odd integer with prime signature {1,1,1} = 3*5*7 = 105

CROSSREFS

Cf. A003961, A025487, A147516.

Sequence in context: A256388 A082897 A147516 * A131822 A131801 A280963

Adjacent sequences:  A233816 A233817 A233818 * A233820 A233821 A233822

KEYWORD

nonn

AUTHOR

Lior Manor, Dec 16 2013

STATUS

approved

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Last modified December 16 09:06 EST 2019. Contains 330020 sequences. (Running on oeis4.)