A272006 a(n) = A003617(n) - A062397(n-1).

0, 0, 0, 8, 6, 2, 2, 18, 6, 6, 18, 2, 38, 36, 30, 36, 60, 2, 2, 50, 38, 116, 8, 116, 6, 12, 66, 102, 330, 318, 56, 32, 48, 60, 192, 68, 66, 42, 132, 2, 120, 108, 62, 56, 30, 8, 120, 32, 192, 8, 150, 120, 326, 170, 30, 20, 2, 278, 158, 18, 6, 92, 446, 120, 56, 48, 48, 48, 98, 8, 32, 272, 38, 78, 206

Offset

1,4

Links

Table of n, a(n) for n=1..75.

Formula

a(n) = A033873(n-1) - 1. - Michel Marcus, Jul 28 2016

Example

For n=4, the smallest 4-digit prime is 1009, and 10^(4-1) + 1 = 1001, so a(4) = 1009 - 1001 = 8. - Michael B. Porter, Aug 01 2016

Mathematica

Table[NextPrime[#] - (# + 1) &[10^(n - 1)], {n, 75}] (* Michael De Vlieger, Jul 13 2016 *)

Prog

(PARI) a(n) = nextprime(10^(n-1)) - (10^(n-1) +  1); \\ Michel Marcus, Jul 28 2016

Crossrefs

Cf. A003617, A033873, A062397.

Sequence in context: A066716 A339801 A360938 * A033952 A365254 A021847

Adjacent sequences: A272003 A272004 A272005 * A272007 A272008 A272009

Keyword

base,nonn

Author

Carauleanu Marc, Jul 13 2016

Status

approved