A080613 - OEIS

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A080613

Minimal sequence such that Omega(a(m))<=Omega(a(n)) for m<n, where Omega=A001222 (sum of exponents in prime factorization).

1, 2, 3, 4, 25, 6, 49, 8, 27, 20, 1331, 12, 2197, 28, 45, 16, 83521, 36, 130321, 40, 189, 88, 279841, 24, 625, 104, 81, 56, 707281, 60, 923521, 32, 891, 272, 4375, 72, 69343957, 304, 1053, 80, 115856201, 168, 147008443, 176, 405, 368, 229345007, 48 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,2`
	COMMENTS	`a(n)=n iff n=2^k or n=3*2^k (A029744); A001222(a(n))=A000523(n).`
	FORMULA	`a(1) = 1, a(n) = if Omega(n)<Omega(a(n-1)) then n*spf(n)^(Omega(a(n-1))-Omega(n)) else n, where spf=A020639 (smallest prime factor).`
	CROSSREFS	`Sequence in context: A171728 A010345 A000336 * A055006 A139050 A043309` `Adjacent sequences: A080610 A080611 A080612 * A080614 A080615 A080616`
	KEYWORD	`nonn`
	AUTHOR	`Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Feb 25 2003`

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Last modified February 17 16:13 EST 2012. Contains 206050 sequences.