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A049059 Third element t of (-1)sigma sociable triple (r,s,t): s=(-1)sigma(r), t=(-1)sigma(s), r=(-1)sigma(t), where if x=Product p(i)^r(i), then (-1)sigma(x)=Product(-1+(Sum p(i)^s(i), s(i)=1 to r(i))). 5
52, 156, 780, 1248, 13260, 19968, 468480 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

EXAMPLE

Factorizations 2^2*13, 2^2*3*13, 2^2*3*5*13, 2^5*3*13, 2^2*3*5*13*17, 2^9*3*13, 2^9*3*5*61

CROSSREFS

Cf. A049057, A049058, A049060.

Sequence in context: A044684 A044384 A044765 * A166390 A161478 A023417

Adjacent sequences:  A049056 A049057 A049058 * A049060 A049061 A049062

KEYWORD

nonn

AUTHOR

Yasutoshi Kohmoto (zbi74583(AT)boat.zero.ad.jp)

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Last modified February 16 07:10 EST 2012. Contains 205874 sequences.