A084398 Except for a(1) = 1, rearrangement of natural numbers such that a(n) is not equal to n, but the prime signature of a(n) is the same as that of n.

1, 3, 2, 9, 7, 10, 5, 27, 4, 6, 13, 18, 11, 15, 14, 81, 19, 12, 17, 28, 22, 21, 29, 40, 49, 33, 8, 20, 23, 42, 37, 243, 26, 35, 34, 100, 31, 39, 38, 24, 43, 30, 41, 45, 44, 51, 53, 80, 25, 52, 46, 50, 47, 56, 57, 54, 55, 62, 61, 84, 59, 58, 68, 729, 69, 70, 71, 63, 65, 66, 67, 108

Offset

1,2

Comments

a(a(n)) = n. - Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jun 20 2003

Links

Paul Tek, Table of n, a(n) for n = 1..10000

Paul Tek, PERL program for this sequence

Example

The first 4 numbers with the prime signature p*q are 6, 10, 14 and 15, so a(6) = 10, a(10) = 6, a(14) = 15 and a(15) = 14.

Prog

(Perl) See Links section.

Crossrefs

Cf. A046523.

Sequence in context: A359036 A021756 A274925 * A118306 A237651 A124003

Adjacent sequences: A084395 A084396 A084397 * A084399 A084400 A084401

Keyword

easy,nonn

Author

Amarnath Murthy, May 31 2003

Extensions

More terms from David Wasserman, Dec 21 2004

Status

approved