id:A141551 - OEIS Search Results

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Numbers n with property that if d divides n, then tau(tau(d)) also divides n.

+0
2

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	OFFSET	`1,2`
	COMMENT	`tau() = A000005().`
	MAPLE	`with(numtheory); isA141551 := proc(n) local dvs, d; dvs := divisors(n) ; for d in dvs do if not tau(tau(d)) in dvs then RETURN(false): fi; od: RETURN(true); end:` `t1:=[]; for n from 1 to 60000 do if isA141551(n) then t1:=[op(t1), n]; fi; od:`
	CROSSREFS	`Cf. A141586.` `Sequence in context: A018894 A056795 A141420 this_sequence A094348 A002182 A077006` `Adjacent sequences: A141548 A141549 A141550 this_sequence A141552 A141553 A141554`
	KEYWORD	`nonn`
	AUTHOR	`N. J. A. Sloane (njas(AT)research.att.com), Sep 12 2008`

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Last modified November 29 12:46 EST 2009. Contains 167659 sequences.

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