A049852 Concatenate "n" and "nextprime(n)".

12, 23, 35, 45, 57, 67, 711, 811, 911, 1011, 1113, 1213, 1317, 1417, 1517, 1617, 1719, 1819, 1923, 2023, 2123, 2223, 2329, 2429, 2529, 2629, 2729, 2829, 2931, 3031, 3137, 3237, 3337, 3437, 3537, 3637, 3741, 3841, 3941, 4041, 4143, 4243

Offset

1,1

Comments

From Petros Hadjicostas, Nov 20 2019: (Start)

Version 1 of the "next prime" function is A007918: smallest prime >= n. PARI/GP's nextprime() is version 1.

Maple's nextprime() is the version 2 that appears in A151800: smallest prime > n. We use version 2 here. (End)

Links

Table of n, a(n) for n=1..42.

Example

From Petros Hadjicostas, Nov 20 2019: (Start)
a(1) = 12 because nextprime(1) = 2.
a(2) = 23 because nextprime(2) = 3.
a(3) = 35 because nextprime(3) = 5.
a(4) = 45 because nextprime(4) = 5.
...
a(10) = 1011 because nextprime(10) = 11.
a(11) = 1113 because nextprime(11) = 13.
... (End)

Maple

a:= n-> parse(cat(n, nextprime(n))):
seq(a(n), n=1..50);  # Alois P. Heinz, Nov 20 2019

Prog

(PARI) a(n) = eval(concat(Str(n), Str(nextprime(n+1)))); \\ Michel Marcus, Jan 01 2017

Crossrefs

Cf. A007918 (version 1 of nextprime), A151800 (version 2 of nextprime).

Sequence in context: A112131 A233032 A088997 * A045532 A255729 A341740

Adjacent sequences: A049849 A049850 A049851 * A049853 A049854 A049855

Keyword

nonn,base

Author

N. J. A. Sloane

Status

approved