A163249 Sum of prime(n) and number of numbers from this set less than n-th nonprime number (A018252(n)).

2, 5, 8, 11, 15, 17, 22, 25, 29, 35, 38, 45, 49, 51, 56, 62, 68, 70, 76, 81, 84, 90, 94, 100, 108, 113, 115, 119, 122, 127, 141, 145, 152, 154, 164, 166, 172, 179, 183, 189, 195, 197, 208, 211, 215, 217, 229, 241, 246, 248

Offset: 1

Author

Jaroslav Krizek, Jul 23 2009

Keywords

• nonn
• uned

Comments

a(n) = Sum of n-th nonprime number (A018252(n)) and number of numbers from this set less than n-th prime (A000040(n)).

Formula

a(n) = prime(n) + A073425(n-1) = A018252(n) + A014689(n) = prime(n) + A018252(n)- n = prime(n) + A002808(n) - n.