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A328398 Maximal digit value in primorial base expansion of A276086(A276086(A276086(n))), where A276086(n) converts primorial base expansion of n into its prime product form. 6
1, 1, 2, 3, 1, 7, 4, 5, 7, 2, 7, 12, 35, 14, 11, 15, 15, 11, 49, 19, 88, 64, 81, 403, 198, 248, 405, 271, 166, 449, 2, 3, 6, 7, 11, 25, 5, 30, 32, 3, 37, 8, 66, 53, 49, 49, 302, 40, 73, 116, 48, 47, 177, 495, 351, 391, 518, 338, 188, 331, 15, 16, 109, 65, 13, 39, 11, 37, 25, 44, 371, 181, 300, 87, 154, 44, 440, 396, 131 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
2's occur at 2, 9, 30, 2312, 2559, 32589, ... (cf. A143293).
In range n = 0 .. 32768, a(n) attains the maximum possible value A000040(A328406(n))-1 only at n=2 and n=2804, when it must be the value of the most significant digit in the primorial base expansion of A328403(n).
When comparing the scatter plots of this sequence and those of A328389 and A328394, although the overall shape gets more blurred on each iteration of A276086, it is easy to see by informal inductive reasoning that the low values of the sequences should occur at about same positions.
Question: Are there any 1's after a(0), a(1) and a(4)?
LINKS
FORMULA
a(n) = A328114(A328403(n)) = A328389(A276087(n)) = A328394(A276086(n)).
For all n, a(n) < A000040(A328406(n)).
MATHEMATICA
Block[{b = MixedRadix[Reverse@ Prime@ Range@ 120], f}, f[n_] := Times @@ Power @@@ # &@ Transpose@{Prime@ Range@ Length@ #, Reverse@ #} &@ IntegerDigits[n, b]; Array[Max@ IntegerDigits[Nest[f, #, 3], b] &, 79, 0]] (* Michael De Vlieger, Oct 17 2019 *)
PROG
(PARI)
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A328114(n) = { my(s=0, p=2); while(n, s = max(s, n%p); n = n\p; p = nextprime(1+p)); (s); };
CROSSREFS
Sequence in context: A263340 A114583 A114581 * A085588 A118008 A256045
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 16 2019
STATUS
approved

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Last modified April 23 01:19 EDT 2024. Contains 371906 sequences. (Running on oeis4.)