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Numbers k for which A276086(k) < k, where A276086 is the primorial base exp-function.
3

%I #7 Feb 05 2022 17:20:02

%S 6,30,31,32,36,60,210,211,212,213,214,215,216,217,218,240,241,242,420,

%T 421,422,2310,2311,2312,2313,2314,2315,2316,2317,2318,2319,2320,2321,

%U 2322,2323,2324,2325,2328,2340,2341,2342,2343,2344,2345,2346,2347,2348,2352,2370,2371,2372,2520,2521,2522,2523,2524,2526,2527

%N Numbers k for which A276086(k) < k, where A276086 is the primorial base exp-function.

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

%t Select[Range[2528], Block[{i, m, n = #, p}, m = i = 1; While[n > 0, p = Prime[i]; m *= p^Mod[n, p]; n = Quotient[n, p]; i++]; m < #] &] (* _Michael De Vlieger_, Feb 05 2022 *)

%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 isA351226(n) = (A276086(n)<n);

%Y Cf. A002110 (subsequence from its third term 6 onward), A276086, A351227 (complement).

%Y Positions of negative terms in A351225, positions of zeros in A351089.

%K nonn,base

%O 1,1

%A _Antti Karttunen_, Feb 05 2022