login
A117300
Consider all pairs (p,q) of consecutive primes such that p and q both have k digits and q-p = k; sequence lists the values of q.
2
3, 13, 19, 31, 43, 61, 73, 1013, 1091, 1097, 1217, 1283, 1301, 1307, 1427, 1433, 1451, 1487, 1493, 1553, 1571, 1583, 1601, 1613, 1667, 1697, 1787, 1871, 1877, 1997, 2003, 2087, 2141, 2207, 2243, 2273, 2297, 2351, 2381, 2393, 2441, 2477, 2543, 2621, 2663
OFFSET
1,1
LINKS
EXAMPLE
31 is in the sequence because (1) it is a 2-digit prime number, (2) the previous 2-digit prime number is 29 and (3) 31-29=2
1451 is in the sequence because (1) it is a 4-digit prime number, (2) the previous 4-digit prime number is 1447 and (3) 1451-1447=4
MATHEMATICA
Transpose[Select[Partition[Prime[Range[400]], 2, 1], IntegerLength[#[[1]]] == IntegerLength[#[[2]]]&&#[[2]]-#[[1]]==IntegerLength[#[[1]]]&]][[2]] (* Harvey P. Dale, Nov 01 2015 *)
CROSSREFS
Cf. A117155.
Sequence in context: A168425 A252090 A079419 * A023215 A185069 A023239
KEYWORD
base,nonn
AUTHOR
Luc Stevens (lms022(AT)yahoo.com), Apr 21 2006
EXTENSIONS
Edited by N. J. A. Sloane, Apr 29 2007
Corrected by Harvey P. Dale, Nov 01 2015
STATUS
approved