A048795 Concatenate p p times, where p runs through the primes.

22, 333, 55555, 7777777, 1111111111111111111111, 13131313131313131313131313, 1717171717171717171717171717171717, 19191919191919191919191919191919191919, 2323232323232323232323232323232323232323232323

Offset

1,1

Links

Table of n, a(n) for n=1..9.

Formula

log a(n) ~ (log 10)n log n. - Charles R Greathouse IV, Sep 20 2012

Example

For each prime number p we write down 'p' p times.
2 -> 22
3 -> 333
5 -> 55555
... -> ...

Maple

a:= n-> (p-> parse(cat(p$p)))(ithprime(n)):
seq(a(n), n=1..10);  # Alois P. Heinz, Jul 07 2016

Mathematica

Table[FromDigits[Flatten[IntegerDigits/@PadRight[{}, p, p]]], {p, Prime[Range[10]]}] (* Harvey P. Dale, Jul 07 2022 *)

Prog

(PARI) a(n) = {p = prime(n); s = Str(p); ss = ""; for (k=1, p, ss = concat(ss, s); ); eval(ss); } \\ Michel Marcus, Jul 02 2016

Crossrefs

Cf. A000040, A000461.

Sequence in context: A053422 A000461 A216730 * A068186 A021284 A019623

Adjacent sequences: A048792 A048793 A048794 * A048796 A048797 A048798

Keyword

nonn,base,easy

Author

Patrick De Geest, Jul 15 1999

Status

approved