The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A241909

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A241909

Self-inverse permutation of natural numbers: a(1)=1, a(p_i) = 2^i, and if n = p_i1 * p_i2 * p_i3 * ... * p_{ik-1} * p_ik, where p's are primes, with their indexes are sorted into nondescending order: i1 <= i2 <= i3 <= ... <= i_{k-1} <= ik, then a(n) = 2^(i1-1) * 3^(i2-i1) * 5^(i3-i2) * ... * p_k^(1+(ik-i_{k-1})). Here k = A001222(n) and ik = A061395(n).
(history; published version)

#54 by Michael De Vlieger at Sun Jul 23 18:24:17 EDT 2023

STATUS

proposed

#53 by Jon E. Schoenfield at Sun Jul 23 15:33:23 EDT 2023

STATUS

editing

#52 by Jon E. Schoenfield at Sun Jul 23 15:33:19 EDT 2023

EXTENSIONS

Typos in the name corrected May 31 2014 by Antti Karttunen, Jan 17 2020

STATUS

approved

#51 by Sean A. Irvine at Thu Jan 23 21:32:05 EST 2020

STATUS

proposed

#50 by Michael De Vlieger at Thu Jan 23 18:02:56 EST 2020

STATUS

editing

#49 by Michael De Vlieger at Thu Jan 23 18:02:52 EST 2020

MATHEMATICA

STATUS

approved

#48 by Susanna Cuyler at Tue Jan 21 18:21:25 EST 2020

STATUS

proposed

#47 by Antti Karttunen at Tue Jan 21 16:26:16 EST 2020

STATUS

editing

#46 by Antti Karttunen at Fri Jan 17 13:59:51 EST 2020

CROSSREFS

Cf. A203623, A241918, A242378, A007814, A064989, A064216, A001222, A061395, A125976, A243060, A243070, A278220, A331280, A331299.

#45 by Antti Karttunen at Fri Jan 17 13:58:45 EST 2020

CROSSREFS

Cf. A203623, A241918, A242378, A007814, A064989, A064216, A001222, A061395, A125976, A243060, A243070.

AUTHOR

Antti Karttunen, May 03 2014, partly inspired by Marc LeBrun's Jan 11 2006 message on SeqFan mailing list. Typos in the name corrected May 31 2014

EXTENSIONS