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 A081761 Least number >n having same type of prime factorization, a(1)=1. 9
 1, 3, 5, 9, 7, 10, 11, 27, 25, 14, 13, 18, 17, 15, 21, 81, 19, 20, 23, 28, 22, 26, 29, 40, 49, 33, 125, 44, 31, 42, 37, 243, 34, 35, 38, 100, 41, 39, 46, 54, 43, 66, 47, 45, 50, 51, 53, 80, 121, 52, 55, 63, 59, 56, 57, 88, 58, 62, 61, 84, 67, 65, 68, 729, 69, 70, 71, 75, 74, 78 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 FORMULA A046523(a(n)) = A046523(n). a(n) = n + A085072(n). - Amiram Eldar, Dec 26 2020 MATHEMATICA sig[n_] := Sort @ FactorInteger[n][[;; , 2]]; a[1] = 1; a[n_] := Module[{sign = sig[n], k = n + 1}, While[sig[k] != sign, k++]; k]; Array[a, 70] (* Amiram Eldar, Dec 26 2020 *) PROG (PARI) a(n) = {if (n==1, 1, my(k=1, s = vecsort(factor(n)[, 2]~)); while (vecsort(factor(n+k)[, 2]~) != s, k++); n+k; )} \\ Michel Marcus, Nov 02 2020 CROSSREFS Cf. A046523, A085072. Sequence in context: A336849 A079427 A168271 * A280702 A269379 A250469 Adjacent sequences:  A081758 A081759 A081760 * A081762 A081763 A081764 KEYWORD nonn AUTHOR Reinhard Zumkeller, Apr 09 2003 STATUS approved

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Last modified July 25 07:08 EDT 2021. Contains 346284 sequences. (Running on oeis4.)