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A343566 Numbers k such that A343564(k) is divisible by 2*k. 1
1, 2, 3, 24, 63, 107, 263, 383, 504, 75414, 17389821, 47574810 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

EXAMPLE

a(4) = 24 is a term because A343564(24) = 96 is divisible by 2*24 = 48.

MAPLE

N:= 100000: # for terms <= N

P:= select(isprime, [seq(i, i=3..2*N)]):

f:= proc(n) local m, Q, q;

  m:= ListTools:-BinaryPlace(P, 2*n);

  Q:= convert(P[1..m], set);

  Q:= Q intersect map(t -> 2*n-t, Q);

  add(2*n mod q, q = Q);

end proc:

A343564:= map(f, [$1..N]):

select(t -> A[t] mod (2*t) = 0, [$1..N]);

CROSSREFS

Cf. A343564.

Sequence in context: A061355 A160618 A279335 * A057665 A157327 A174073

Adjacent sequences:  A343563 A343564 A343565 * A343567 A343568 A343569

KEYWORD

nonn,more

AUTHOR

J. M. Bergot and Robert Israel, Apr 20 2021

EXTENSIONS

a(11) and a(12) from Martin Ehrenstein, Apr 25 2021

STATUS

approved

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Last modified May 20 23:05 EDT 2022. Contains 353886 sequences. (Running on oeis4.)