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A360526 Odd numbers k such that A360522(k) > 2*k. 2

%I #9 Feb 11 2023 07:56:43

%S 15015,19635,21945,23205,25935,26565,31395,33495,33915,35805,39585,

%T 41055,42315,42735,45885,47355,49665,50505,51765,54285,55965,58695,

%U 61215,64155,68145,70455,72345,77385,80535,82005,83265,84315,91245,95865,102795,112035,116655

%N Odd numbers k such that A360522(k) > 2*k.

%C First differs from A112643, A129485, A249263 at n = 46: a(46) = 165165 is not a term of these sequences.

%H Amiram Eldar, <a href="/A360526/b360526.txt">Table of n, a(n) for n = 1..10000</a>

%e 15015 is a term since A360522(15015) = 32256 > 2*15015.

%t f[p_, e_] := p^e + e; s[1] = 1; s[n_] := Times @@ f @@@ FactorInteger[n]; q[n_] := s[n] > 2*n; Select[Range[1, 10^5, 2], q]

%o (PARI) isab(n) = { my(f = factor(n)); prod(i = 1, #f~, f[i,1]^f[i,2] + f[i,2]) > 2*n;}

%o is(n) = n%2 && isab(n);

%Y Cf. A360522.

%Y Subsequence of A005101, A005231 and A360525.

%Y Similar sequences: A094889, A127666, A129485, A293186, A321147, A348275, A348605.

%K nonn

%O 1,1

%A _Amiram Eldar_, Feb 10 2023

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Last modified September 13 13:43 EDT 2024. Contains 375908 sequences. (Running on oeis4.)