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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 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.)