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A242458 Numbers n such that integer part of the square root of n appears in the middle of decimal expansion of n. 1
1, 1360, 1361, 1362, 1363, 1364, 1365, 1366, 1367, 1368, 1370, 1371, 1372, 1373, 1374, 1375, 1376, 1377, 1378, 1379, 2490, 2491, 2492, 2493, 2494, 2495, 2496, 2497, 2498, 2499, 2500, 2501, 2502, 2503, 2504, 2505, 2506, 2507, 2508, 2509, 3590, 3591, 3592, 3593 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Subsequence of A133785.

LINKS

Michel Lagneau, Table of n, a(n) for n = 1..9445

EXAMPLE

a(2)=1360 because [sqrt(1360)] = 36 occurs in the middle of 1360.

MATHEMATICA

lst={}; Do[a=IntegerDigits[n]; b=Length[a]; c=IntegerLength[Floor[Sqrt[n]]]; If[EvenQ[b-c]&&FromDigits[Take[a, {(b-c)/2+1, (b+c)/2}]]==Floor[Sqrt[n]], AppendTo[lst, n]], {n, 10^5}]; lst

CROSSREFS

Cf. A133785.

Sequence in context: A252379 A175696 A023091 * A223254 A260441 A265498

Adjacent sequences:  A242455 A242456 A242457 * A242459 A242460 A242461

KEYWORD

nonn,base

AUTHOR

Michel Lagneau, Jun 08 2014

STATUS

approved

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Last modified August 20 22:45 EDT 2019. Contains 326155 sequences. (Running on oeis4.)