The OEIS is supported by the many generous donors to the OEIS Foundation.

 Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”). Other ways to Give
 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A066740 Number of distinct partitions of A007504(n) which can be obtained by merging parts in the partition 2+3+5+...+prime(n), where prime(n) is the n-th prime. 1
 1, 1, 2, 5, 13, 44, 151, 614, 2446, 11066, 53368, 253927, 1316375, 7213979 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS EXAMPLE For n=4, the 13 partitions are 17, 2+15, 3+14, 5+12, 7+10, 8+9, 2+3+12, 2+5+10, 2+7+8, 3+5+9, 3+7+7, 5+5+7, 2+3+5+7. 5+12 and 7+10 can be obtained in two ways each: 5+12 = (5)+(2+3+7) = (2+3)+(5+7), 7+10 = (7)+(2+3+5) = (2+5)+(3+7). MAPLE b:= proc(n) local p; p:= `if`(n=0, 1, ithprime(n)); b(n):= `if`(n<2, {[p\$n]}, map(x-> [sort([x[], p]), seq(sort(subsop(i=x[i]+p, x)), i=1..nops(x))][], b(n-1))) end: a:= n-> nops(b(n)): seq(a(n), n=0..10); # Alois P. Heinz, May 31 2013 MATHEMATICA addto[ p_, k_ ] := Module[ {}, lth=Length[ p ]; Union[ Sort/@Append[ Table[ Join[ Take[ p, i-1 ], {p[ [ i ] ]+k}, Take[ p, i-lth ] ], {i, 1, lth} ], Append[ p, k ] ] ] ]; addtolist[ plist_, k_ ] := Union[ Join@@(addto[ #, k ]&/@plist) ]; l[ 0 ]={{}}; l[ n_ ] := l[ n ]=addtolist[ l[ n-1 ], Prime[ n ] ]; a[ n_ ] := Length[ l[ n ] ] CROSSREFS Cf. A007504, A066723. Sequence in context: A287023 A287008 A119533 * A212825 A212826 A212827 Adjacent sequences: A066737 A066738 A066739 * A066741 A066742 A066743 KEYWORD more,nonn AUTHOR Naohiro Nomoto, Jan 16 2002 EXTENSIONS Edited by Dean Hickerson, Jan 18 2002 STATUS approved

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

Last modified December 5 07:25 EST 2022. Contains 358582 sequences. (Running on oeis4.)