OFFSET
1,1
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10841 (terms <= 10^5, first 1000 terms from Donovan Johnson)
P. De Geest, WONplate 122
C. Rivera, Puzzle 46
Eric Weisstein's World of Mathematics, Prime Sums
FORMULA
A084143(a(n)) > 1. - Ray Chandler, Sep 20 2023
EXAMPLE
36 = (17 + 19) = (5 + 7 + 11 + 13) or (#2,17) (#4,5).
MATHEMATICA
m=5!; lst={}; Do[p=Prime[a]; Do[p+=Prime[b]; If[p<Prime[m]*3+8, AppendTo[lst, p]], {b, a+1, m, 1}], {a, m}]; lst1=Sort[lst]; lst={}; Do[If[lst1[[n]]==lst1[[n+1]], AppendTo[lst, lst1[[n]]]], {n, Length[lst1]-1}]; Union[lst] (* Vladimir Joseph Stephan Orlovsky, Aug 15 2009 *)
PROG
(PARI) upto(n) = {my(s = 0, pr = List([0]), l = List(), res = List()); forprime(p = 2, n + 100, s+=p; listput(pr, s) ); for(i = 3, #pr, for(j = 2, i-1, if(pr[i] - pr[i-j] <= n, listput(l, pr[i] - pr[i-j]) , next(2) ) ) ); listsort(l); for(i = 2, #l, if(l[i-1] == l[i], listput(res, l[i]) ) ); Set(res); } \\ David A. Corneth, Aug 22 2019
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Patrick De Geest, Feb 04 2002
EXTENSIONS
Offset corrected by Donovan Johnson, Nov 14 2013
STATUS
approved