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A343185 Numbers k such that 2*k is a multiple of A045917(k). 1
2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 15, 16, 18, 19, 30, 33, 34, 35, 36, 40, 44, 45, 46, 56, 60, 70, 76, 80, 92, 100, 112, 114, 128, 130, 140, 145, 148, 182, 184, 209, 210, 221, 228, 238, 247, 270, 276, 286, 297, 324, 344, 372, 399, 408, 410, 425, 429, 437, 444, 460, 468, 475, 504, 506, 507, 510 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..600

EXAMPLE

a(4) = 5 is a term because 2*5 = 10 is a multiple of A045917(5) = 2.

MAPLE

P:= select(isprime, [2, seq(i, i=3..2000, 2)]):

filter:= proc(n) local k1, k2;

   k1:= ListTools:-BinaryPlace(P, n+1);

   k2:= ListTools:-BinaryPlace(P, 2*n+1);

   2*n mod nops(convert(P[1..k1], set) intersect map(t -> 2*n-t, convert(P[k1..k2], set))) = 0

end proc:

select(filter, [$2..1000]);

CROSSREFS

Cf. A045917.

Sequence in context: A243463 A247805 A164713 * A070331 A080672 A056757

Adjacent sequences:  A343182 A343183 A343184 * A343186 A343187 A343188

KEYWORD

nonn

AUTHOR

J. M. Bergot and Robert Israel, Apr 18 2021

STATUS

approved

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Last modified September 22 22:38 EDT 2021. Contains 347609 sequences. (Running on oeis4.)