OFFSET
1,9
COMMENTS
Greatest common divisor of two consecutive primes after each prime is written backward.
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
Neither of these common divisors are divisible by 3 or by 10 or by 11.
MAPLE
A103163 := proc(n)
p := ithprime(n) ;
q := nextprime(p) ;
igcd(digrev(p), digrev(q)) ;
end proc:
seq(A103163(n), n=1..114) ; # R. J. Mathar, Sep 22 2018
MATHEMATICA
rd[x_] :=FromDigits[Reversed[IntegerDigits[x]]]; Table[GCD[rd[Prime[w]], rd[Prime[w+1]]], {w, 1, 1000}]
GCD@@#&/@(Partition[IntegerReverse/@Prime[Range[120]], 2, 1]) (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jan 31 2020 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Labos Elemer, Jan 27 2005
EXTENSIONS
Edited by Jon E. Schoenfield, Oct 26 2019
STATUS
approved