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A181820 a(1) = 1; for n > 1, if A025487(n) = Product p(i)^e(i), then a(n) = Product p(e(i)). 11
1, 2, 3, 4, 5, 6, 7, 10, 8, 11, 9, 14, 12, 13, 15, 22, 20, 17, 21, 18, 26, 16, 25, 28, 19, 33, 30, 34, 24, 35, 44, 23, 39, 42, 38, 40, 55, 27, 52, 29, 50, 51, 36, 49, 66, 46, 56, 65, 45, 68, 31, 70, 57, 32, 60, 77, 78, 58, 88, 85, 63, 76, 37, 110, 69, 48, 84, 91, 75, 102, 62, 54, 98, 104, 95 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
A permutation of the positive integers.
The partition given by the prime signature of A025487(n) has Heinz number a(n). - Pontus von Brömssen, Mar 25 2023
LINKS
FORMULA
a(n) = A181819(A025487(n)).
a(n) = A122111(A181815(n)).
EXAMPLE
A025487(8) = 24 = 2^3*3 has the exponents (3,1) in its canonical prime factorization. Accordingly, a(8) = prime(3)*prime(1) (i.e., A000040(3)*A000040(1)), which equals 5*2=10.
CROSSREFS
A181815 is another mapping from the members of A025487 to the positive integers. Also see A181819, A181821.
Cf. A000040, A122111, A361808 (inverse), A361809 (fixed points).
Sequence in context: A368431 A194963 A072794 * A371249 A354369 A199426
KEYWORD
nonn
AUTHOR
Matthew Vandermast, Dec 07 2010
STATUS
approved

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Last modified March 29 05:16 EDT 2024. Contains 371264 sequences. (Running on oeis4.)