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A038544
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a(n) = Sum_{i=0..10^n} i^3.
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4
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1, 3025, 25502500, 250500250000, 2500500025000000, 25000500002500000000, 250000500000250000000000, 2500000500000025000000000000, 25000000500000002500000000000000, 250000000500000000250000000000000000, 2500000000500000000025000000000000000000
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OFFSET
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0,2
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COMMENTS
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These terms k = x.y satisfy Diophantine equation x.y = (x+y)^2, when x and y have the same number of digits, "." means concatenation, and y may not begin with 0. So, this is a subsequence of A350870 and A238237. - Bernard Schott, Jan 20 2022
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LINKS
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Table of n, a(n) for n=0..10.
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FORMULA
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a(n) = (10^n+1)^2 * 10^(2*n) / 4.
From Bernard Schott, Jan 20 2022: (Start)
a(n) = A037156(n)^2.
a(n) = A350869(n) + 10^(3*n). (End)
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EXAMPLE
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a(1) = Sum_{i=0..10} i^3 = (Sum_{i=0..10} i)^2 = 3025.
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PROG
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(PARI) sumcu(n) = for(x=0, n, y=10^x; z=y^2*(y+1)^2/4; (print1(z", "))) - Cino Hilliard, Jun 18 2007
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CROSSREFS
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Cf. A037156, A238237, A350869, A350870.
Sequence in context: A225996 A167044 A221249 * A252142 A031553 A031733
Adjacent sequences: A038541 A038542 A038543 * A038545 A038546 A038547
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KEYWORD
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easy,nonn
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AUTHOR
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Marvin Ray Burns
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EXTENSIONS
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Edited by N. J. A. Sloane, Jul 02 2008 at the suggestion of R. J. Mathar
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STATUS
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approved
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