A122408 Numbers n such that A067824(n) = n.

1, 2, 4, 6, 8, 16, 32, 40, 64, 128, 224, 256, 264, 512, 1024, 2048, 4096, 5632, 8192, 16384, 26624, 32768, 65536, 72192, 131072, 154752, 262144, 524288, 557056, 1048576, 2072576, 2097152, 2490368, 4194304, 5537792, 8388608, 10518528, 16777216, 33554432, 48234496

Offset

1,2

Links

Amiram Eldar, Table of n, a(n) for n = 1..100

Formula

A002033(a(n)) = A074206(a(n)) = a(n)/2.

A067824(a(n)) = a(n).

Example

m=40, the proper divisors of 40 are 1, 2, 4, 5, 8, 10 and 20:
A067824(40) = 1+Sum(A067824(d): 1<=d<40) = 1+(1+2+4+2+8+6+16) = 40, therefore 40 is a term.

Crossrefs

A000079 is a subsequence.

Cf. A002033, A067824, A074206, A163272.

Sequence in context: A368325 A324579 A271520 * A326037 A100055 A334031

Adjacent sequences: A122405 A122406 A122407 * A122409 A122410 A122411

Keyword

nonn

Author

Reinhard Zumkeller, Sep 03 2006

Extensions

More terms from Amiram Eldar, Aug 31 2019

Status

approved