login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A225627 a(n) = lcm(A000793(n),p1,p2,...,pk) for such a partition {p1+p2+...+pk} of n that maximizes this value among all partitions of n. 4
1, 1, 2, 6, 12, 30, 30, 84, 120, 180, 210, 420, 660, 780, 1260, 4620, 5460, 5460, 5460, 9240, 13860, 13860, 16380, 32760, 120120, 180180, 180180, 235620, 180180, 471240, 1021020, 1021020, 1141140, 1141140, 2282280, 2282280, 4476780, 4476780, 6846840, 6846840 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Row 2 of A225630.

This could be called a "twice-iterated Landau's function."

LINKS

Table of n, a(n) for n=0..39.

Index entries for sequences related to lcm's

FORMULA

a(n) = A225636(n)*A000793(n).

PROG

(Scheme):

(define (A225627 n) (let ((maxlcm (list 0))) (fold_over_partitions_of n (A000793 n) lcm (lambda (p) (set-car! maxlcm (max (car maxlcm) p)))) (car maxlcm)))

(define (fold_over_partitions_of m initval addpartfun colfun) (let recurse ((m m) (b m) (n 0) (partition initval)) (cond ((zero? m) (colfun partition)) (else (let loop ((i 1)) (recurse (- m i) i (+ 1 n) (addpartfun i partition)) (if (< i (min b m)) (loop (+ 1 i))))))))

CROSSREFS

Cf. A000793, A225630, A225628, A225629, A225636.

Sequence in context: A229487 A195166 A225646 * A237704 A181826 A143176

Adjacent sequences:  A225624 A225625 A225626 * A225628 A225629 A225630

KEYWORD

nonn

AUTHOR

Antti Karttunen, May 13 2013

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 20 00:28 EST 2019. Contains 320329 sequences. (Running on oeis4.)