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A145522 a(n) is such that A145521(n) = A053810(a(n)). 1
1, 3, 2, 6, 5, 4, 10, 23, 12, 7, 39, 9, 97, 24, 164, 484, 2759, 5044, 109, 32334, 114605, 216960, 8, 14, 252, 785135, 5503557, 28, 39222428, 75703838, 548300521, 1496 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

This sequence is a permutation of the positive integers. It is its own inverse permutation.

LINKS

Table of n, a(n) for n=1..32.

EXAMPLE

The primes raised to prime exponents form the sequence, when the terms are arranged in numerical order, 4,8,9,25,27,32,49,121,125,128,...(sequence A053810). The 10th term is 128, which is 2^7. So the 10th term of sequence A145521 is 7^2 = 49. 49 is the 7th term of A053810. So a(10) = 7 and a(7) = 10.

PROG

(PARI) lista(nn) = {my(c, m); for(k=1, nn, if(isprime(isprimepower(k, &p)), c=0; m=bigomega(k)^p; forprime(q=2, sqrtint(m), c+=primepi(logint(m, q))); print1(c, ", "))); } \\ Jinyuan Wang, Feb 25 2020

CROSSREFS

Cf. A053810, A145521.

Sequence in context: A194909 A038722 A277881 * A283939 A293056 A131968

Adjacent sequences:  A145519 A145520 A145521 * A145523 A145524 A145525

KEYWORD

nonn,more

AUTHOR

Leroy Quet, Oct 12 2008

EXTENSIONS

a(11)-a(28) from Ray Chandler, Nov 01 2008

a(29)-a(32) from Jinyuan Wang, Feb 25 2020

STATUS

approved

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Last modified June 22 12:56 EDT 2021. Contains 345380 sequences. (Running on oeis4.)