id:A131420 - OEIS Search Results

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A tabular sequence of arrays counting ordered factorizations over least prime signatures. The unordered version is described by sequence A129306.

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1, 2, 3, 4, 8, 13, 8, 20, 44, 75, 26, 16, 48, 132, 308, 541, 76, 176, 32, 112, 368, 1076, 2612, 4683, 208, 604, 1460, 252, 818, 64, 256, 876, 3408, 10404, 25988, 47293, 544, 1888, 5740, 14300, 768, 2316, 3172, 7880, 128, 576, 2496, 10096, 36848, 116180 (list; graph; listen)

	OFFSET	`1,2`
	COMMENT	`The display has 1 2 3 5 7 11 15 ... terms per column. (cf A000041)` `The arrays begin` `1.....2.....4......8......16.....32.....64......128` `.....3.....8.....20......48....112....256......576` `..........13.....44.....132....368....976.....2496` `.................75.....308...1076...3408....10096` `........................541...2612...10404...36848` `..............................4683...25988..116180` `.....................................47293..296564` `............................................545835` `.................26......96....208.....544` `........................176....604.....1888` `..............................1460.....5740` `......................................14300` `...............................252......269` `.......................................2316` `...............................818.....3172` `.......................................7880` `with column sums` `1....5....25....173....1297....12225....124997 => A035341`
	EXAMPLE	`36 = 223*3 and is in A025487. There are 26 ways to factor 36 so a(11) = 26.`
	CROSSREFS	`Cf. A000041 A000670 A002033 A025487 A035098 A035341 A050324 A074206 A095705 A098348 A104725 A108464 A129306.` `Sequence in context: A057608 A060984 A098348 this_sequence A095705 A034776 A068791` `Adjacent sequences: A131417 A131418 A131419 this_sequence A131421 A131422 A131423`
	KEYWORD	`nonn`
	AUTHOR	`Alford Arnold (Alford1940(AT)aol.com), Jul 10 2007`

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Last modified December 3 01:16 EST 2008. Contains 151161 sequences.

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