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A242255 Primes-greedy summable primes, as defined at A242252. 5
5, 7, 13, 19, 31, 43, 61, 73, 103, 109, 139, 149, 151, 181, 191, 193, 199, 229, 241, 251, 271, 283, 293, 313, 347, 349, 419, 421, 431, 433, 463, 523, 557, 571, 587, 601, 619, 641, 643, 661, 701, 719, 797, 811, 821, 823, 829, 839, 859, 883, 929, 1021, 1031 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See A242252 for the definitions of greedy sum and summability.  A242255 and A242256 partition the primes.

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..500

EXAMPLE

Four primes-greedy primes with matching prime-greedy sums are shown here:

a(1) = 5 = 3 + 2

a(2) = 7 = 5 + 2

a(3) = 13 = 11 + 2

a(12) = 149 = 139 + 7 + 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, A242253, A242254, A242256, A241833, A000040.

Sequence in context: A189441 A106986 A218011 * A006512 A074304 A264865

Adjacent sequences:  A242252 A242253 A242254 * A242256 A242257 A242258

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, May 09 2014

STATUS

approved

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Last modified April 18 03:59 EDT 2021. Contains 343072 sequences. (Running on oeis4.)