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Numbers k for which A276086(k) <= A002620(k), where A276086 is the primorial base exp-function and A002620(k) = floor(k^2/4).
4

%I #16 Mar 12 2024 09:53:25

%S 6,7,8,12,30,31,32,33,34,35,36,37,38,39,40,42,43,60,61,62,63,64,65,66,

%T 67,68,72,90,91,92,93,96,120,210,211,212,213,214,215,216,217,218,219,

%U 220,221,222,223,224,225,226,227,228,229,230,231,232,234,235,240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255

%N Numbers k for which A276086(k) <= A002620(k), where A276086 is the primorial base exp-function and A002620(k) = floor(k^2/4).

%H Antti Karttunen, <a href="/A328118/b328118.txt">Table of n, a(n) for n = 1..10000</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 A002620(n) = ((n^2)>>2);

%o isA328118(n) = (A276086(n) <= A002620(n));

%Y Cf. A002620, A276086, A328119 (complement).

%Y Subsequences: A328110 (after its two initial terms), A351228, A370127.

%K nonn

%O 1,1

%A _Antti Karttunen_, Oct 08 2019