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A165286
Primes which are the sum of two or more consecutive terms of A072055.
1
23, 61, 83, 101, 139, 157, 197, 263, 283, 293, 331, 349, 367, 383, 401, 449, 491, 509, 541, 569, 571, 577, 641, 659, 661, 701, 751, 773, 809, 811, 853, 859, 881, 887, 967, 977, 997, 1009, 1039, 1069, 1117, 1123, 1181, 1193, 1217, 1237, 1279, 1283, 1361
OFFSET
1,1
COMMENTS
The terms in A072055 are odd, so the count of terms in the sum must be odd to yield a prime.
EXAMPLE
a(1)= 5+7+11 = sum_{i=1..3} A072055(i) = 23.
a(2) = sum_{i=1..5} A072055(i) = 5+7+11+15+23 = 61. a(3) = 7+11+15+23+27 = 83.
MATHEMATICA
lst={}; Do[s=2*Prime[m]+1; Do[p=Prime[n]; s+=(2*p+1); If[PrimeQ[s], If[s<=6949, AppendTo[lst, s]]], {n, m+1, 6!}], {m, 1, 6!}]; lst=Take[Union@lst, 200]
Module[{nn=100, terms}, terms=2*Prime[Range[nn]]+1; Take[Union[Select[ Flatten[ Table[Total/@Partition[terms, n, 1], {n, 3, nn, 2}]], PrimeQ]], nn/2]] (* Harvey P. Dale, Jun 11 2015 *)
CROSSREFS
Sequence in context: A080822 A068363 A351377 * A031342 A215166 A141870
KEYWORD
nonn
AUTHOR
EXTENSIONS
Redefined in terms of A072055; cross-references to unrelated sequences deleted - R. J. Mathar, Sep 16 2009
STATUS
approved