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A048795 Concatenate p p times, where p runs through the primes. 0
22, 333, 55555, 7777777, 1111111111111111111111, 13131313131313131313131313, 1717171717171717171717171717171717, 19191919191919191919191919191919191919, 2323232323232323232323232323232323232323232323 (list; graph; refs; listen; history; text; internal format)
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

P:=proc(i) local a, b, c, n; for n from 1 by 1 to i do a:=ithprime(n); b:=a-1; c:=a; while b>0 do c:=a+c*10^floor(evalf((log10(a)+1), 100)); b:=b-1; od; print(c); od; end: P(100); # Paolo P. Lava, Jan 21 2009

# second Maple program:

a:= n-> (p-> parse(cat(p$p)))(ithprime(n)):

seq(a(n), n=1..10);  # Alois P. Heinz, Jul 07 2016

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

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Last modified April 17 11:50 EDT 2021. Contains 343064 sequences. (Running on oeis4.)