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A089779 Let n range through the odd numbers skipping multiples of 5; a(n) = n-th prime ending in n. 2
11, 23, 107, 179, 2411, 3413, 5417, 4919, 6121, 5923, 9127, 8629, 9931, 10133, 10937, 11939, 14741, 14243, 16747, 16649, 16451, 18553, 19157, 19259, 22961, 22963, 24767, 25169, 28571, 24373, 28277, 31079, 30181, 29483, 31687, 33589, 33091 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

2411 is the 11th prime ending in 11: (11, 211, ..., 2111, 2311, 2411)

MAPLE

f:= proc(n) local d, k, count;

d:= 10^(ilog10(n)+1);

count:= 0;

for k from 0 while count < n do

   if isprime(k*d+n) then count:= count+1 fi

od;

(k-1)*d+n

end proc:

seq(seq(f(10*i+j), j=[1, 3, 7, 9]), i=0..10); # Robert Israel, Dec 10 2017

MATHEMATICA

NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; f[n_] := Block[{p = 2, c = 0, m = Floor[ Log[10, n] + 1]}, While[ If[ Mod[p, 10^m] == n, c++ ]; c < n, p = NextPrim[p]]; p]; Map[f, Select[ Table[n, {n, 1, 91, 2}], Mod[ #, 10] != 5 &]] (* Robert G. Wilson v, Nov 26 2003 *)

CROSSREFS

Sequence in context: A294255 A088777 A041238 * A146084 A179520 A288406

Adjacent sequences:  A089776 A089777 A089778 * A089780 A089781 A089782

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Nov 24 2003

EXTENSIONS

Extended by Robert G. Wilson v, Nov 26 2003

STATUS

approved

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Last modified May 21 00:41 EDT 2019. Contains 323427 sequences. (Running on oeis4.)