OFFSET
1,1
COMMENTS
All the terms in sequence are even numbers, but none are congruent to 4 mod 10.
LINKS
K. D. Bajpai, Table of n, a(n) for n = 1..5550
EXAMPLE
6 is in the sequence because the concatenation of 6^2 and 6 + 1 gives 367, which is prime.
30 is in the sequence because the concatenation of 30^2 and 31 gives 90031, which is prime.
34 is not in the sequence because the concatenation of 34^2 and 35 gives 115635 = 3 * 5 * 13 * 593.
MAPLE
KD := proc() local a, b; a:=parse(cat(n^2, n+1)); if isprime(a) then RETURN (n); fi; end: seq(KD(), n=1..2000);
CROSSREFS
KEYWORD
nonn,base,less
AUTHOR
K. D. Bajpai, Dec 07 2013
STATUS
approved