The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 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 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

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