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A155074
Primes that appear as a substring in the concatenation of primes.
0
23, 31, 71, 113, 131, 167, 271, 293, 317, 347, 359, 373, 379, 389, 491, 571, 631, 673, 677, 719, 761, 773, 811, 877, 911, 929, 937, 941, 971, 983, 997, 1031, 1091, 1103, 1171, 1193, 1223, 1231, 1283, 1291, 1361, 1409, 1433, 1511, 1523, 1531, 1571, 1607
OFFSET
1,1
COMMENTS
Start with a blank concatenation string S. Does prime p(1)=2 appear in string S? No. Concatenate 2 to string S. Does prime p(2)=3 appear in string S="2"? No. Concatenate 3 to string S. Does prime p(3)=5 appear in string S="23"? No. Concatenate 5 to string S. and so on Does prime p(9)=23 appear in string S="235711131719"? Yes. 23 is in the sequence. Do not concatenate 23 to string S.
EXAMPLE
a(1)= 23 because 23 appears in the string 235711131719. a(3)= 71 because 71 appears in the string 235711131719293741434753596167. (Notice "23" is omitted from the string here: 235711131719--293741434753596167.)
CROSSREFS
Sequence in context: A165985 A093014 A165450 * A105007 A243438 A154291
KEYWORD
easy,nonn,base
AUTHOR
Gil Broussard, Jan 19 2009
STATUS
approved