

A185949


Smallest prime ending in 10^n+1 in its base10 representation.


0



11, 101, 21001, 1810001, 2100001, 61000001, 2010000001, 11100000001, 61000000001, 1810000000001, 14100000000001, 151000000000001, 5010000000000001, 9100000000000001, 271000000000000001, 1110000000000000001, 24100000000000000001, 261000000000000000001, 3910000000000000000001, 11100000000000000000001
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


LINKS

Table of n, a(n) for n=1..20.


MATHEMATICA

Table[k=0; While[!PrimeQ[p=FromDigits[Join[IntegerDigits[k], IntegerDigits[10^n+1]]]], k++]; p, {n, 20}]


PROG

(Python)
# This implementation assumes function is_prime(n)
# returns True if n is prime, or False otherwise:
for n in range (1, 100):
....pattern = 10**n + 1
....for j in range (0, 10000000):
........if (j == 0):
............num = "%d" % (pattern)
........else:
............num = "%d%d" % (j, pattern)
........if (is_prime(num)):
............print num
............break


CROSSREFS

Sequence in context: A199304 A156668 A103992 * A001387 A247863 A180280
Adjacent sequences: A185946 A185947 A185948 * A185950 A185951 A185952


KEYWORD

nonn,base


AUTHOR

Amir H. Farrahi, Feb 07 2011


STATUS

approved



