A091762 Last n digits of concatenation of first n primes.

2, 23, 235, 2357, 35711, 571113, 7111317, 11131719, 113171923, 1317192329, 31719232931, 171923293137, 7192329313741, 19232931374143, 923293137414347, 2329313741434753, 32931374143475359, 293137414347535961, 9313741434753596167, 31374143475359616771, 137414347535961677173, 3741434753596167717379

Offset: 1

Author

Reinhard Zumkeller, Feb 04 2004

Keywords

• nonn
• base
• easy

Comments

a(n) = A019518(n) mod 10^n; a(n) mod 10^A055642(A000040(n)) = A000040(n); for the primes in this sequence see A091763.

Examples

			The first 5 primes are 2, 3, 5, 7, 11. The last 5 digits concatenated are 35711 so a(5) = 35711. - _David A. Corneth_, Sep 15 2019
		

Links

• David A. Corneth, Table of n, a(n) for n = 1..1000
• Eric Weisstein's World of Mathematics, Consecutive Number Sequences

Programs

Mathematica

Table[FromDigits[Take[Flatten[IntegerDigits/@Prime[Range[n]]],-n]],{n,20}] (* Harvey P. Dale, Sep 15 2019 *)

PARI

a(n) = {my(p = prime(n), v = digits(p)); while(#v < n, p = precprime(p - 1); v = concat(digits(p), v)); fromdigits(vector(n, i, v[#v - n + i]))} \\ David A. Corneth, Sep 15 2019

Extensions

More terms from David A. Corneth, Sep 15 2019