A287353 a(0)=0; for n>0, a(n) = 10*a(n-1) + prime(n).

0, 2, 23, 235, 2357, 23581, 235823, 2358247, 23582489, 235824913, 2358249159, 23582491621, 235824916247, 2358249162511, 23582491625153, 235824916251577, 2358249162515823, 23582491625158289

Offset: 0

Author

Luke Zieroth, May 23 2017

Keywords

• nonn
• easy

Links

• Michael De Vlieger, Table of n, a(n) for n = 0..1000

Crossrefs

Cf. A014824, A019518, A092844, A110299.

Cf. A379426 (prime terms).

Programs

Mathematica

FoldList[10 #1 + Prime@ #2 &, 0, Range@ 17] (* Michael De Vlieger, May 24 2017 *)

PARI

a(n) = fromdigits(primes(n)); \\ Kevin Ryde, Jun 22 2022

Python

from sympy import prime
l = [0]
for i in range(20):
    l += [10 * l[i] + prime(i + 1)]
print(l) # Indranil Ghosh, May 25 2017

Formula

a(n) = Sum_{i=1..n} 10^(n-i)*prime(i), n >= 1. - Ya-Ping Lu, Dec 24 2024