Smallest square beginning with concatenation of first n natural numbers.

0

`%I #14 Jan 28 2024 20:57:03
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`%S 1,121,12321,1234321,123454321,12345654321,1234567654321,
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`%T 123456787654321,12345678987654321,1234567891022847726601,
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`%U 12345678910116040727447056,12345678910111210088193915136,1234567891011121368630088707263161,12345678910111213145200045239801398529
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`%N Smallest square beginning with concatenation of first n natural numbers.
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`%e a(3) = 12321 = 111^2.
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`%e a(10) = 1234567891022847726601 = 35136418301^2. [Corrected by _Sean A. Irvine_, Jan 28 2024]
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`%Y Cf. A007908.
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`%K base,easy,nonn
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`%O 1,2
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`%A _Amarnath Murthy_, Feb 20 2002
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`%E More terms from _Ralf Stephan_, Oct 12 2002
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`%E a(10) corrected and a(14) by _Sean A. Irvine_, Jan 28 2024
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