A060245 Primes p such that the sum of the first p composite numbers is itself prime.

5, 17, 37, 43, 47, 53, 73, 101, 127, 149, 283, 439, 601, 881, 967, 991, 1087, 1117, 1129, 1201, 1259, 1277, 1303, 1319, 1453, 1481, 1559, 1571, 1607, 1721, 1973, 2293, 2341, 2351, 2381, 2411, 2591, 2677, 2729, 2741, 2957, 2971, 3049, 3167, 3457, 3491

Offset

1,1

Links

Table of n, a(n) for n=1..46.

Mathematica

f[ n_Integer ] := Block[ {k = n + PrimePi[ n ] + 1}, While[ k - PrimePi[ k ] - 1 != n, k++ ]; k ]; s = 0; Do[ s = s + f[ n ]; If[ PrimeQ[ n ] && PrimeQ[ s ], Print[ n ] ], {n, 1, 5000} ]

Crossrefs

Sequence in context: A145689 A321658 A080167 * A119456 A264904 A257582

Adjacent sequences: A060242 A060243 A060244 * A060246 A060247 A060248

Keyword

nonn

Author

Robert G. Wilson v, Mar 22 2001

Status

approved