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Numbers n such that the decimal expansion of n^2 contains n+1.
2

%I #11 Oct 22 2018 22:33:17

%S 11,76,101,759,1001,2434,3826,5618,10001,36559,47576,62511,67947,

%T 68443,82621,100001,105125,312511,684429,880618,1000001,4687499,

%U 5123596,7130618,8703826,10000001,26452434,33620473,38837976,39904875,43605459,54687499,86421306,100000001

%N Numbers n such that the decimal expansion of n^2 contains n+1.

%C a(n)^2 is a subsequence of A186774, in particular A186774(a(n)) = a(n)^2. For k > 0, 10^k+1 is a term.

%H Chai Wah Wu, <a href="/A282384/b282384.txt">Table of n, a(n) for n = 1..70</a>

%e 76 is a term since 76^2 = 5776 contains 77 = 76+1.

%o (Python)

%o A282384_list = [i for i in range(1,10**6) if str(i+1) in str(i**2)]

%Y Cf. A186774.

%K nonn

%O 1,1

%A _Chai Wah Wu_, Feb 13 2017