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A178496
The smallest palindromic prime which contains the decimal expansion of 11^n in its decimal representation.
0
11, 11, 1212121, 133111331, 361464163, 31501610513, 916517717715619, 1017178491948717101, 111888534121435888111, 1967497532357947691, 11064247395259374246011, 142853116706111607611358241
OFFSET
0,1
COMMENTS
The entries have two possible formats: a//11^n ( = 11^n//b), where the double-slash denotes concatenation, or c//11^n//d.
By definition, the concatenation has to be a palindromic prime, A002385.
EXAMPLE
a(0) = 11^0//1 = 1//1 = palprime(5).
a(1) = 11^1 = 11.
a(2) = 1212//11^2 = 1212//121 = palprime(151).
a(3) = 13311//11^3 = 13311//1331 = palprime(1270).
a(4) = 36//11^4//63 = 36//14641//63 = palprime(3035).
a(5) = 3150//11^5//3 = 3150//161051//3 = palprime(18465).
a(6) = 9165177//11^6//9 = 9165177//1771561//9.
a(7) = 101717849//11^7//01 = 101717849//19487171//01.
a(8) = 1118885341//11^8//11 = 1118885341//214358881//11.
a(9) = 196749753//11^9 = 196749753//2357947691.
a(10) = 11064247395//11^10//1 = 11064247395//25937424601//1.
a(11) = 14//11^11//1607611358241 = 14//285311670611//1607611358241.
a(12) = 111276738248//11^12//11 = 111276738248//3138428376721//11.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Ulrich Krug (leuchtfeuer37(AT)gmx.de), May 28 2010
STATUS
approved