A364565 Numbers k at which point A364557 (the Möbius transform of A005941) is equal to A000010 (Euler phi function).

1, 2, 3, 4, 5, 6, 8, 10, 12, 16, 20, 24, 32, 40, 48, 64, 80, 85, 96, 128, 160, 170, 192, 256, 320, 340, 384, 512, 640, 680, 768, 1024, 1280, 1360, 1536, 2048, 2560, 2720, 3072, 4096, 5120, 5440, 6144, 8192, 10240, 10880, 12288, 16384, 20480, 21760, 24576, 32768, 40960, 43520, 49152, 65536, 81920, 87040, 98304, 131072

Offset

1,2

Comments

Question: Are there any other odd terms apart from 1, 3, 5, 85?

Links

Table of n, a(n) for n=1..60.

Prog

(PARI)
A364557(n) = if(1==n, 1, 2^(primepi(vecmax(factor(n)[, 1]))+(bigomega(n)-omega(n))-1));
isA364565(n) = (A364557(n)==eulerphi(n));

Crossrefs

Positions of 0's in A364558.

Cf. A000010, A029747, A364557, A364566.

Sequence in context: A362127 A364960 A245709 * A364548 A364544 A253789

Adjacent sequences: A364562 A364563 A364564 * A364566 A364567 A364568

Keyword

nonn

Author

Antti Karttunen, Jul 29 2023

Status

approved