A270777 -id:A270777 - cp's OEIS frontend

A270653 Integers k such that A003266(k) is divisible by k.

1, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80

Offset: 1

Altug Alkan, Mar 20 2016

nonn

Note that this sequence is not the complement of A000057.

See A230359 for the prime terms of this sequence.

			11 is a term because 1*1*2*3*5*8*13*21*34*55*89 is divisible by 11.

Amiram Eldar, Table of n, a(n) for n = 1..10000

Complement of A270777.

Cf. A000057, A003266, A230359.

Select[Range@ 80, Divisible[Fibonorial@ #, #] &] (* Version 10, or *) Select[Range@ 80, Divisible[Product[Fibonacci@ k, {k, #}], #] &] (* Michael De Vlieger, Mar 23 2016 *)

t(n) = prod(k=1, n, Mod(fibonacci(k), n));
for(n=1, 1e2, if(lift(t(n)) == 0, print1(n, ", ")));

A270839 Integers k such that (A003266(k)/A000045(k-1)) is not divisible by k.

Original entry on oeis.org

2, 3, 4, 7, 9, 11, 19, 23, 31, 43, 59, 67, 71, 79, 83, 103, 127, 131, 163, 167, 179, 191, 223, 227, 239, 251, 271, 283, 311, 359, 367, 379, 383, 419, 431, 439, 443, 463, 467, 479, 487, 491, 499, 503, 523, 547, 571, 587, 599, 607, 631, 643, 647, 659, 683, 719, 727, 739, 751, 787, 823, 827, 839

Offset: 1

Altug Alkan, Mar 23 2016

nonn

A270777 is a subsequence.

It appears that this sequence generates prime numbers except 4 and 9. [Verified for the first 500 terms. - Amiram Eldar, Apr 01 2021]

			3 is a term because 1*2 is not divisible by 3.
7 is a term because 1*1*2*3*5*13 is not divisible by 7.

Amiram Eldar, Table of n, a(n) for n = 1..500

Cf. A000045, A000057, A003266, A270777.

Select[Range[2, 840], ! Divisible[Fibonorial@ #/Fibonacci[# - 1], #] &] (* Version 10, or *) Select[Range[2, 840], ! Divisible[Product[Fibonacci@ k, {k, #}]/Fibonacci[# - 1], #] &] (* Michael De Vlieger, Mar 24 2016 *)

t(n) = fibonacci(n) * prod(k=1, n-2, Mod(fibonacci(k), n));
for(n=2, 1e3, if(lift(t(n)) != 0, print1(n, ", ")));

Offset corrected by Amiram Eldar, Apr 01 2021

cp's OEIS Frontend

A270653 Integers k such that A003266(k) is divisible by k.

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