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A242253 Number of primes in the primes-greedy sum (defined at A242252) for the n-th odd prime. 5
1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 3, 2, 2, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

See A242252 for the definition of primes-greedy sum.

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..2000

EXAMPLE

n ... n-th odd prime .. primes-greedy sum... a(n)

2 ... 5 ............... 3 + 2 .............. 2

3 ... 7 ............... 5 + 2 .............. 2

4 ... 11 .............. 7 + 3 .............. 2

5 ... 13 .............. 11 + 2 ............. 2

34 .. 149 ............. 139 + 7 + 3 ........ 3

MATHEMATICA

z = 200;  s = Table[Prime[n], {n, 1, z}]; t = Table[{s[[n]], #, Total[#] == s[[n]]} &[   DeleteCases[-Differences[FoldList[If[#1 - #2 >= 0, #1 - #2, #1] &, s[[n]], Reverse[Select[s, # < s[[n]] &]]]], 0]], {n, z}]; r[n_] := s[[n]] - Total[t[[n]][[2]]]; tr =  Table[r[n], {n, 2, z}]  (* A242252 *)

c = Table[Length[t[[n]][[2]]], {n, 2, z}] (* A242253 *)

f = 1 + Flatten[Position[tr, 0]]  (* A242254 *)

Prime[f]  (* A242255 *)

f1 = Prime[Complement[Range[Max[f]], f]] (* A242256 *)

(* Peter J. C. Moses, May 06 2014 *)

CROSSREFS

Cf. A242252, A242254, A242255, A242256, A241833, A000040.

Sequence in context: A071702 A225541 A076303 * A071839 A235044 A163857

Adjacent sequences:  A242250 A242251 A242252 * A242254 A242255 A242256

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, May 09 2014

STATUS

approved

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Last modified October 14 01:36 EDT 2019. Contains 327994 sequences. (Running on oeis4.)