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Smallest triangular number that contains the string n in its exact center.
5

%I #14 Dec 26 2018 03:34:34

%S 0,1,120,3,741,153,6,171,780,190,10,111156,1128,131328,2145,15,3160,

%T 1176,4186,101926,152076,21,1225,102378,3240,5253,7260,1275,28,232903,

%U 113050,9316,1326,133386,2346,5356,36,1378,7381,133903,3403,2415,124251,1431,6441

%N Smallest triangular number that contains the string n in its exact center.

%H Jon E. Schoenfield, <a href="/A062690/b062690.txt">Table of n, a(n) for n = 0..10000</a>

%e a(13)=131328 is the smallest triangular number that contains the digit string '13' in its exact center.

%Y Cf. A018855, A062829.

%K easy,nonn,base

%O 0,3

%A _Erich Friedman_, Jul 04 2001

%E Corrected by _Harvey P. Dale_, Jul 20 2001

%E a(42)-a(44) from _Jon E. Schoenfield_, Dec 25 2018