A003991 - OEIS

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A003991 as a simple table

`n`		`a(n)`
`1`		`1`
`2`		`2`
`3`		`2`
`4`		`3`
`5`		`4`
`6`		`3`
`7`		`4`
`8`		`6`
`9`		`6`
`10`		`4`
`11`		`5`
`12`		`8`
`13`		`9`
`14`		`8`
`15`		`5`
`16`		`6`
`17`		`10`
`18`		`12`
`19`		`12`
`20`		`10`
`21`		`6`
`22`		`7`
`23`		`12`
`24`		`15`
`25`		`16`
`26`		`15`
`27`		`12`
`28`		`7`
`29`		`8`
`30`		`14`
`31`		`18`
`32`		`20`
`33`		`20`
`34`		`18`
`35`		`14`
`36`		`8`
`37`		`9`
`38`		`16`
`39`		`21`
`40`		`24`
`41`		`25`
`42`		`24`
`43`		`21`
`44`		`16`
`45`		`9`
`46`		`10`
`47`		`18`
`48`		`24`
`49`		`28`
`50`		`30`
`51`		`30`
`52`		`28`
`53`		`24`
`54`		`18`
`55`		`10`
`56`		`11`
`57`		`20`
`58`		`27`
`59`		`32`
`60`		`35`
`61`		`36`
`62`		`35`
`63`		`32`
`64`		`27`
`65`		`20`
`66`		`11`
`67`		`12`
`68`		`22`
`69`		`30`
`70`		`36`
`71`		`40`
`72`		`42`
`73`		`42`
`74`		`40`
`75`		`36`
`76`		`30`
`77`		`22`
`78`		`12`

[1,2,2,3,4,3,4,6,6,4,5,8,9,8,5,6,10,12,12,10,6,7, 12,15,16,15,12,7,8,14,18,20,20,18,14,8,9,16,21,24, 25,24,21,16,9,10,18,24,28,30,30,28,24,18,10,11,20, 27,32,35,36,35,32,27,20,11,12,22,30,36,40,42,42, 40,36,30,22,12]

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Last modified April 19 16:52 EDT 2024. Contains 371794 sequences. (Running on oeis4.)