A393040 - OEIS

A393040

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

6, 8, 30, 32, 36, 60, 64, 210, 212, 213, 214, 216, 224, 240, 243, 270, 420, 432, 450, 630, 2310, 2312, 2313, 2314, 2315, 2316, 2317, 2318, 2319, 2320, 2322, 2324, 2325, 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

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OFFSET

1,1

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10535

Index entries for sequences related to primorial base.

PROG

(PARI)

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

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

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

(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));

CROSSREFS

Cf. A276086, A348507.

Subsequence of A393070.

Subsequences: A351228, A392602.

Sequence in context: A000773 A258283 A039720 * A056097 A099431 A323201

Adjacent sequences: A393037 A393038 A393039 * A393041 A393042 A393043

KEYWORD

nonn,base

AUTHOR

Antti Karttunen, Feb 08 2026

STATUS

approved