The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A329344 Number of times most frequent primorial is present in the greedy sum of primorials adding to A108951(n). 9

%I #11 Nov 18 2019 22:18:21

%S 1,1,1,2,1,2,1,1,1,2,1,4,1,2,6,2,1,2,1,4,6,2,1,3,4,2,1,4,1,5,1,1,6,2,

%T 8,4,1,2,6,1,1,1,1,4,5,2,1,3,6,8,6,4,1,2,4,8,6,2,1,3,1,2,3,2,13,12,1,

%U 4,6,5,1,3,1,2,5,4,16,12,1,2,6,2,1,2,11,2,6,8,1,10,12,4,6,2,7,6,1,12,10,6,1,12,1,8,4

%N Number of times most frequent primorial is present in the greedy sum of primorials adding to A108951(n).

%C The greedy sum is also the sum with the minimal number of primorials, used for example in the primorial base representation.

%H Antti Karttunen, <a href="/A329344/b329344.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>

%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>

%H <a href="/index/Pri#primorial_numbers">Index entries for sequences related to primorial numbers</a>

%F a(n) = A328114(A108951(n)) = A051903(A324886(n)).

%e For n = 24 = 2^3 * 3, A108951(24) = A034386(2)^3 * A034386(3) = 2^3 * 6 = 48 = 30 + 6 + 6 + 6, and as the most frequent primorial in the sum is 6 = A002110(2), we have a(24) = 3.

%t With[{b = Reverse@ Prime@ Range@ 120}, Array[Max@ IntegerDigits[#, MixedRadix[b]] &@ Apply[Times, Map[#1^#2 & @@ # &, FactorInteger[#] /. {p_, e_} /; e > 0 :> {Times @@ Prime@ Range@ PrimePi@ p, e}]] &, 105] ] (* _Michael De Vlieger_, Nov 18 2019 *)

%o (PARI)

%o A034386(n) = prod(i=1, primepi(n), prime(i));

%o A108951(n) = { my(f=factor(n)); prod(i=1, #f~, A034386(f[i, 1])^f[i, 2]) }; \\ From A108951

%o A328114(n) = { my(s=0, p=2); while(n, s = max(s,(n%p)); n = n\p; p = nextprime(1+p)); (s); };

%o A329344(n) = A328114(A108951(n));

%o (PARI)

%o A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };

%o A324886(n) = A276086(A108951(n));

%o A051903(n) = if((1==n),0,vecmax(factor(n)[, 2]));

%o A329344(n) = A051903(A324886(n));

%Y Cf. A002110, A034386, A051903, A108951, A276086, A324886, A324888, A328114, A329040, A329045, A329343, A329348, A329349.

%K nonn

%O 1,4

%A _Antti Karttunen_, Nov 11 2019

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 7 09:14 EDT 2024. Contains 373161 sequences. (Running on oeis4.)