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 A328406 The length of primorial base expansion (number of significant digits) of A276086(A276086(A276086(n))), where A276086(n) converts primorial base expansion of n into its prime product form. 7
 2, 3, 2, 3, 3, 7, 4, 5, 6, 3, 7, 8, 12, 8, 7, 12, 12, 7, 17, 11, 25, 21, 24, 84, 49, 63, 94, 67, 49, 97, 4, 6, 8, 9, 7, 10, 6, 14, 13, 4, 14, 11, 22, 22, 19, 20, 66, 16, 23, 40, 20, 19, 50, 105, 81, 87, 104, 71, 49, 81, 12, 10, 34, 21, 9, 16, 11, 23, 16, 17, 85, 49, 71, 27, 44, 21, 93, 87, 39, 58, 171, 50, 205, 112, 54, 78, 78 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS Antti Karttunen, Table of n, a(n) for n = 0..32768 FORMULA a(n) = A235224(A328403(n)) = A328404(A276087(n)) = A328405(A276086(n)). For all n, A000040(a(n)) > A328398(n). MATHEMATICA Block[{b = MixedRadix[Reverse@ Prime@ Range@ 120], f}, f[n_] := Times @@ Power @@@ # &@ Transpose@ {Prime@ Range@ Length@ #, Reverse@ #} &@ IntegerDigits[n, b]; Array[IntegerLength[Nest[f, #, 3], b] &, 87, 0]] (* Michael De Vlieger, Oct 17 2019 *) PROG (PARI) A235224(n) = { my(s=0, p=2); while(n, s++; n = n\p; p = nextprime(1+p)); (s); }; A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); }; A328403(n) = A276086(A276086(A276086(n))); A328406(n) = A235224(A328403(n)); CROSSREFS Cf. A235224, A276086, A276087, A328398, A328403, A328404, A328405. Sequence in context: A300651 A003051 A305866 * A257396 A293519 A237582 Adjacent sequences:  A328403 A328404 A328405 * A328407 A328408 A328409 KEYWORD nonn AUTHOR Antti Karttunen, Oct 16 2019 STATUS approved

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Last modified June 16 21:29 EDT 2021. Contains 345080 sequences. (Running on oeis4.)