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A375432
Numbers k such that A375428(k) > A375430(k).
1
8, 24, 27, 32, 40, 54, 56, 64, 72, 88, 96, 104, 108, 120, 125, 135, 136, 152, 160, 168, 184, 189, 192, 200, 216, 224, 232, 243, 248, 250, 256, 264, 270, 280, 288, 296, 297, 312, 320, 328, 343, 344, 351, 352, 360, 375, 376, 378, 392, 408, 416, 424, 440, 448, 456
OFFSET
1,1
COMMENTS
First differs from A374590 at n = 31.
For numbers k that are not in this sequence A375428(k) = A375430(k).
Numbers k such that A051903(k)+1 is not of the form Fibonacci(m)-1, m >= 3.
The asymptotic density of this sequence is 1 - 1/zeta(2) - Sum_{k>=4} (1/zeta(Fibonacci(k)) - 1/zeta(Fibonacci(k)-1)) = 0.12330053981922224451... .
LINKS
EXAMPLE
8 is a term since A375428(8) = 3 > 2 = A375430(8).
MATHEMATICA
fibQ[n_] := n >= 2 && Or @@ IntegerQ /@ Sqrt[5*n^2 + {-4, 4}]; Select[Range[300], !fibQ[Max[FactorInteger[#][[;; , 2]]] + 1] &]
PROG
(PARI) isfib(n) = n >= 2 && (issquare(5*n^2-4) || issquare(5*n^2+4));
is(n) = n > 1 && !isfib(vecmax(factor(n)[, 2]) + 1);
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Amiram Eldar, Aug 15 2024
STATUS
approved