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A295562 List of numbers k such that the middle Fibonomial coefficient (2n,n)_F is prime to 105. 0
1, 1312, 3256, 3257, 3936, 3937, 4000, 4001, 4032, 38880, 38881, 39000, 39001, 19928280, 19928281, 21975136, 21975137, 21975305, 21975312, 22054032 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

From Charlie Neder, Mar 04 2019: (Start)

For the middle Fibonomial coefficient (2n,n)_F to be coprime to a prime p, we must have that the integral part of n/A001177(p) has its base-p digits all < p/2 and its fractional part is < 1/2.

Next term > 10^8. (End)

LINKS

Table of n, a(n) for n=1..20.

Christian Ballot, Divisibility of the middle Lucasnomial coefficient, Fib. Q., 55 (2017), 297-308.

FORMULA

Numbers k congruent to 0 or 1 modulo 8 such that floor(k/4) is in A005836, k is in A037543, and floor(k/8) is in A037461. - Charlie Neder, Mar 04 2019

CROSSREFS

Cf. A003267, A030979.

Sequence in context: A205301 A320506 A322834 * A030646 A223612 A223413

Adjacent sequences:  A295559 A295560 A295561 * A295563 A295564 A295565

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Nov 28 2017

EXTENSIONS

a(10)-a(20) from Charlie Neder, Mar 04 2019

STATUS

approved

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Last modified December 1 11:35 EST 2021. Contains 349429 sequences. (Running on oeis4.)