A178137 Partial sums of A068148.

2, 5, 10, 17, 28, 51, 94, 161, 250, 351, 460, 671, 894, 1127, 1560, 2003, 2680, 3467, 4344, 5231, 6240, 7349, 8472, 9695, 11806, 14027, 16360, 19581, 22904, 26247, 29680, 34247, 39690, 47479, 55356, 64243, 73242, 82243, 91254, 101141, 111042

Offset: 1

Author

Jonathan Vos Post, May 20 2010

Keywords

• base
• easy
• nonn

Comments

Partial sums of primes in which neighboring digits differ at most by 1 (neighbors of 9 are 0 and 8 and 9). The subsequence of primes in this partial sum begins: 5, 17, 2003, 3467, 5231, 7349, 101141, 187367. What is the smallest value in this partial sum (after 5) which is itself a prime in which neighboring digits differ at most by 1? What is the analog in other bases?

Examples

			a(16) = 2 + 3 + 5 + 7 + 11 + 23 + 43 + 67 + 89 + 101 + 109 + 211 + 223 + 233 + 433 + 443 = 2003 is prime.
		

Crossrefs

Cf. A000040, A007504 - Sum of first n primes, A068148.

Programs

Mathematica

Accumulate[Select[Prime[Range[1500]],Max[Abs[Differences[ IntegerDigits[ #]]] /.{9->1}] <2&]] (* Harvey P. Dale, Apr 01 2019 *)

Formula

a(n) = SUM[i=1..n] A068148(i).