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A318971 Primes that divide at least one term of A318970. 2
3, 29, 31821709567, 28480625878963 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No other terms below 10^14.

If prime p does not divide any of the first A227944(p) <= log2(p) terms of A318970, then p does not divide any term of A318970, i.e., p does not belong to this sequence.

(2^260+5)/261 is a term (76-digit prime). Hence, a(5) <= (2^260+5)/261.

Any prime p with A318989(p)=0 belongs to this sequence. However, it is unknown if there is a term p with nonzero A318989(p).

LINKS

Table of n, a(n) for n=1..4.

Max Alekseyev, Iterations of 2^(n-1)+5: the strong law of small numbers, or something bigger?, MathOverflow, 2016.

EXAMPLE

a(1)=3 divides A318970(k) for all k >= 1.

a(2)=29 divides A318970(k) for all k >= 3.

a(3)=31821709567 divides A318970(k) for all k >= 8.

a(4)=28480625878963 divides A318970(k) for all k >= 11.

CROSSREFS

Cf. A227944, A245594, A318970, A318989.

Sequence in context: A112981 A178336 A176495 * A082792 A078242 A108739

Adjacent sequences:  A318968 A318969 A318970 * A318972 A318973 A318974

KEYWORD

nonn,more,hard

AUTHOR

Max Alekseyev, Sep 06 2018

STATUS

approved

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Last modified April 15 07:59 EDT 2021. Contains 342975 sequences. (Running on oeis4.)