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A086536 Least common multiple of numbers obtained by adding one to the odd divisors of n and subtracting 1 from the even divisors of n. 0
2, 2, 4, 6, 6, 20, 8, 42, 20, 18, 12, 660, 14, 104, 48, 210, 18, 340, 20, 342, 88, 84, 24, 106260, 78, 350, 140, 2808, 30, 20880, 32, 6510, 204, 198, 72, 78540, 38, 740, 280, 31122, 42, 234520, 44, 3612, 5520, 360, 48, 4994220, 200, 11466, 468, 17850, 54 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..53.

FORMULA

a(n) = least common multiple of (Ea-1), (Eb-1), (Ec-1), ..., (Oa+1), (Ob+1), (Oc+1)..., where Ea, Eb, Ec, ... and Oa, Ob, Oc, ... are respectively the even and odd divisors of n.

EXAMPLE

a(14) = 104. The divisors of 14 are 1,2,7 and 14 and the corresponding numbers obtained are 2,1,8 and 13 whose least common multiple is 104.

PROG

(PARI) a(n) = local(d); d = divisors(n); l = 1; for (i = 1, length(d), if (d[i]%2, d[i]++, d[i]--); l = lcm(l, d[i])); l; (Wasserman)

CROSSREFS

Cf. A086535.

Sequence in context: A102425 A162608 A143216 * A053045 A152424 A145804

Adjacent sequences:  A086533 A086534 A086535 * A086537 A086538 A086539

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Aug 18 2003

EXTENSIONS

More terms from David Wasserman, Mar 15 2005

STATUS

approved

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Last modified December 9 21:41 EST 2016. Contains 278987 sequences.