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A305183 Least k such that A048272(k) = -n. 0
2, 4, 8, 16, 24, 64, 48, 256, 96, 144, 192, 4096, 240, 16384, 768, 576, 480, 262144, 720, 1048576, 960, 2304, 12288, 16777216, 1440, 5184, 49152, 3600, 3840, 1073741824, 2880, 4294967296, 3360, 36864, 786432, 20736, 5040, 274877906944, 3145728, 147456, 6720, 4398046511104, 11520, 17592186044416 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

All terms are even.

LINKS

Table of n, a(n) for n=0..43.

FORMULA

a(n) = 2 * A187941(n).

a(n) = 4 * A005179(n) for n > 0.

PROG

(PARI) a048272(n) = sumdiv(n, d, if (d%2, 1, -1));

a(n) = {my(k=1); while (a048272(k) != -n, k++); k; } \\ Michel Marcus, May 27 2018

CROSSREFS

Cf. A005179, A187941.

Cf. A038547 (similar but with n instead of -n)

Sequence in context: A182763 A272709 A119311 * A112992 A202274 A070789

Adjacent sequences:  A305180 A305181 A305182 * A305184 A305185 A305186

KEYWORD

nonn

AUTHOR

Seiichi Manyama, May 26 2018

STATUS

approved

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Last modified September 19 23:59 EDT 2019. Contains 327207 sequences. (Running on oeis4.)