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A092949
Numbers of the form prime(n+1) + prime(n) + 1.
1
6, 9, 13, 19, 25, 31, 37, 43, 53, 61, 69, 79, 85, 91, 101, 113, 121, 129, 139, 145, 153, 163, 173, 187, 199, 205, 211, 217, 223, 241, 259, 269, 277, 289, 301, 309, 321, 331, 341, 353, 361, 373, 385, 391, 397, 411, 435, 451, 457, 463, 473, 481, 493, 509, 521
OFFSET
1,1
LINKS
Carlos Rivera, Puzzle 1021. p(k)+p(k+1)+1, The Prime Puzzles and Problems Connection. A puzzle about these numbers.
FORMULA
a(n) = A001043(n) + 1. - Michel Marcus, Mar 15 2020
MAPLE
seq( ithprime(x)+ithprime(x+1)+1, x=1..80);
MATHEMATICA
Total/@Partition[Prime[Range[60]], 2, 1]+1 (* Harvey P. Dale, Jun 24 2015 *)
PROG
(Sage)
BB = primes_first_n(56)
L = []
for i in range(55):
L.append(BB[1+i]+BB[i]+1)
L # Zerinvary Lajos, Jun 27 2008
(PARI) a(n) = prime(n+1)+prime(n)+1; \\ Michel Marcus, Mar 15 2020
CROSSREFS
Cf. A001043.
Sequence in context: A315967 A315968 A315969 * A048626 A002598 A315970
KEYWORD
nonn
AUTHOR
Jorge Coveiro, Apr 19 2004
STATUS
approved