A049851 Concatenate prevprime(n) and n.

23, 34, 35, 56, 57, 78, 79, 710, 711, 1112, 1113, 1314, 1315, 1316, 1317, 1718, 1719, 1920, 1921, 1922, 1923, 2324, 2325, 2326, 2327, 2328, 2329, 2930, 2931, 3132, 3133, 3134, 3135, 3136, 3137, 3738, 3739, 3740, 3741, 4142, 4143, 4344

Offset

3,1

Links

Harvey P. Dale, Table of n, a(n) for n = 3..1000

Mathematica

Table[NextPrime[n, -1]*10^IntegerLength[n]+n, {n, 3, 50}] (* Harvey P. Dale, Aug 16 2024 *)

Prog

(PARI) a(n) = eval(concat(Str(precprime(n-1)), Str(n))); \\ Michel Marcus, Aug 11 2017

Crossrefs

Cf. A151799.

Sequence in context: A145566 A146595 A230123 * A353087 A223606 A120147

Adjacent sequences: A049848 A049849 A049850 * A049852 A049853 A049854

Keyword

nonn,base

Author

N. J. A. Sloane

Status

approved