login
A129748
Numbers n such that the sum of the first n primes with the final digit 9 is prime.
0
1, 3, 7, 11, 13, 19, 37, 39, 61, 73, 89, 107, 109, 113, 117, 147, 153, 159, 171, 173, 207, 241, 253, 307, 311, 329, 347, 419, 429, 461, 481, 491, 497, 509, 523, 529, 539, 543, 559, 613, 617, 631, 651, 691, 701, 703, 731, 737, 741, 753, 799, 809, 813, 823, 827
OFFSET
1,2
FORMULA
a(n)=primes in A030433 added to obtain A129081(n)
MATHEMATICA
Position[Accumulate[Select[Prime[Range[5000]], Last[ IntegerDigits[#]] == 9&]], _?PrimeQ]//Flatten (* Harvey P. Dale, Aug 23 2017 *)
CROSSREFS
KEYWORD
easy,base,less,nonn
AUTHOR
Tomas Xordan, May 14 2007
STATUS
approved