A393040 - OEIS

%I #11 Feb 10 2026 22:21:08

%S 6,8,30,32,36,60,64,210,212,213,214,216,224,240,243,270,420,432,450,

%T 630,2310,2312,2313,2314,2315,2316,2317,2318,2319,2320,2322,2324,2325,

%U 2328,2340,2342,2343,2344,2346,2348,2349,2352,2370,2372,2376,2400,2520,2522,2523,2524,2526,2528,2532,2550,2552,2556,2560,2730

%N Numbers k such that A276086(k) <= A348507(k).

%H Antti Karttunen, <a href="/A393040/b393040.txt">Table of n, a(n) for n = 1..10535</a>

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

%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 A348507(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1]++); (factorback(f)-n); };

%o is_A393040(n) = (A276086(n) <= A348507(n));

%o (PARI) is_A393040(n) = if(!n, 0, my(f=factor(n), u=A348507(n), m=1, p=2, orgn=n); while(n, m *= (p^(n%p)); if(m>u, return(0)); n \= p; p = nextprime(1+p)); (1));

%Y Cf. A276086, A348507.

%Y Subsequence of A393070.

%Y Subsequences: A351228, A392602.

%K nonn,base

%O 1,1

%A _Antti Karttunen_, Feb 08 2026