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A339973 Numbers k for which A019565(2k)-1 is a multiple of A000265(phi(A019565(2k))). 4
0, 1, 2, 3, 4, 8, 16, 20, 32, 33, 34, 35, 38, 41, 50, 56, 64, 128, 176, 256, 259, 290, 512, 1024, 2048, 2056, 2081, 2089, 2096, 2180, 4096, 4130, 8192, 9218, 16384, 18436, 32768, 65536, 131072, 131140, 262144, 279552, 524288, 524308, 524546, 1048576, 1048736, 2097152, 4194304, 4194352, 4194420, 4196656, 4202499, 8388608 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Numbers k such that A339971(k) divides A339809(2k).

Union of {0}, A000079 and the terms of (1/2)*A048675(A339880(i)), for i >= 1, sorted into ascending order.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..94

PROG

(PARI)

A019565(n) = { my(m=1, p=1); while(n>0, p = nextprime(1+p); if(n%2, m *= p); n >>= 1); (m); };

isA339971(n) = { my(x=A019565(2*n)); !((x-1)%A000265(eulerphi(x))); };

CROSSREFS

Positions of zeros in A339898, and of ones in A339901.

Cf. A000010, A000265, A048675, A339821, A339880, A339809, A339971, A339974.

Cf. A000079 (subsequence).

Cf. also A339816, A339906.

Sequence in context: A189740 A118841 A126294 * A224912 A162724 A244750

Adjacent sequences:  A339970 A339971 A339972 * A339974 A339975 A339976

KEYWORD

nonn

AUTHOR

Antti Karttunen, Dec 26 2020

STATUS

approved

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Last modified April 21 23:52 EDT 2021. Contains 343156 sequences. (Running on oeis4.)