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A167860 Primes p dividing every A167859(m) from m=(p-1)/2 to m=(p-1). 4
7, 47, 191, 383, 439, 1151, 1399, 2351, 2879, 3119, 3511, 3559 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Apparently A167860 is a subset of primes of the form 8n+7 (A007522).

A167859(n) = 4^n*Sum_{ k=0..n } ((binomial(2*k,k))^2)/4^k.

Every A167859(m) from m=(p-1)/2 to m=(p-1) is divisible by prime p belonging to A167860.

7^3 divides A167859(13) and 7^2 divides A167859(10)-A167859(13).

Every A167859(m) from m=(kp-1 - (p-1)/2) to m=(kp-1) is divisible by prime p from A167860.

Every A167859(m) from m=((p^2-1)/2) to m=(p^2-1) is divisible by prime p from A167860. For p=7 every A167859(m) from m=((p^3-1)/2) to m=(p^3-1) and from m=((p^4-1)/2) to m(p^4-1)is divisible by p^2.

LINKS

Table of n, a(n) for n=1..12.

CROSSREFS

Cf. A000984, A066796, A006134, A082590, A132310, A002457, A144635, A167713, A167859, A007522.

Sequence in context: A142185 A158914 A046872 * A152988 A201437 A202509

Adjacent sequences:  A167857 A167858 A167859 * A167861 A167862 A167863

KEYWORD

more,nonn

AUTHOR

Alexander Adamchuk, Nov 13 2009

STATUS

approved

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Last modified June 4 11:32 EDT 2020. Contains 334825 sequences. (Running on oeis4.)