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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A125746 a(n) is the smallest positive integer such that (sum{k|n, 1<=k<=a(n)} k) is >= n. 2
1, 2, 3, 4, 5, 3, 7, 8, 9, 10, 11, 6, 13, 14, 15, 16, 17, 9, 19, 10, 21, 22, 23, 8, 25, 26, 27, 14, 29, 15, 31, 32, 33, 34, 35, 12, 37, 38, 39, 20, 41, 21, 43, 44, 45, 46, 47, 16, 49, 50, 51, 52, 53, 27, 55, 28, 57, 58, 59, 20, 61, 62, 63, 64, 65, 33, 67, 68, 69, 35, 71, 24, 73 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

EXAMPLE

The divisors of 12 are 1,2,3,4,6,12. 1+2+3+4 = 10, which is smaller than 12; but 1+2+3+4+6 = 16, which is >= 12. So a(12) = 6.

MATHEMATICA

f[n_] := Block[{k = 1, d = Divisors[n]}, While[Sum[d[[i]], {i, k}] < n, k++ ]; d[[k]]]; Table[f[n], {n, 76}] (*Chandler*)

CROSSREFS

Cf. A125747, A117553.

Sequence in context: A034699 A111615 A053627 * A143055 A017890 A134011

Adjacent sequences:  A125743 A125744 A125745 * A125747 A125748 A125749

KEYWORD

nonn

AUTHOR

Leroy Quet Dec 05 2006

EXTENSIONS

Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Dec 06 2006

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 17 14:50 EST 2012. Contains 206050 sequences.