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A309770
Numbers that are sums of one or more consecutive primes in more than one way.
1
5, 17, 23, 31, 36, 41, 53, 59, 60, 67, 71, 72, 83, 90, 97, 100, 101, 109, 112, 119, 120, 127, 131, 138, 139, 143, 152, 173, 180, 181, 187, 197, 199, 204, 210, 211, 221, 223, 228, 233, 240, 251, 258, 263, 269, 271, 276, 281, 287, 300, 304, 311, 323, 330, 331, 340, 349
OFFSET
1,1
COMMENTS
Contains A067372 as a subsequence.
LINKS
Eric Weisstein's World of Mathematics, Prime Sums
FORMULA
A054845(a(n)) > 1.
EXAMPLE
5 is in the sequence because it can be written as either 5 or 2 + 3.
36 is the sequence because it can be written as either 5 + 7 + 11 + 13 or 17 + 19.
MAPLE
N:= 1000: # for terms <= N
P:= select(isprime, [2, seq(i, i=3..N, 2)]):
S:= [0, op(ListTools:-PartialSums(P))]:
V:= Vector(N):
for i from 1 to nops(S) do
for j from i-1 to 1 by -1 do
v:= S[i]-S[j];
if v > N then break fi;
V[v]:= V[v]+1;
od od:
select(t -> V[t]>1, [$1..N]); # Robert Israel, Aug 22 2019
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Aug 16 2019
STATUS
approved