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 A007475 a(n) is the smallest positive number such that the sum of A001032(n) consecutive squares starting with a(n)^2 is a square. (Formerly M3043) 3
 1, 3, 18, 7, 1, 25, 7, 539, 25, 7, 22, 442, 225, 192, 13, 15, 26914, 244, 50, 5552, 30, 553, 7, 4493, 83342, 83, 65, 775, 3807, 64, 556, 20, 106, 132, 2277, 15, 1788, 5063, 27, 11320, 280, 358, 1805, 210, 9985, 802, 183, 71752, 10123, 16806, 94707486, 1081 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 REFERENCES N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS Christopher E. Thompson, Table of n, a(n) for n = 1..10438 Laurent Beeckmans, Squares Expressible as Sum of Consecutive Squares, Am. Math. Monthly, Volume 101, Number 5, pp. 437-442, May 1994. EXAMPLE a(3)=18 because A001032(3)=11 and the sum of 11 squares 18^2 + 19^2 + ... + 28^2 = 77^2. CROSSREFS Cf. A001032. Square roots of sum are in A076215. Sequence in context: A120647 A131635 A324554 * A324889 A281791 A281722 Adjacent sequences:  A007472 A007473 A007474 * A007476 A007477 A007478 KEYWORD nonn AUTHOR EXTENSIONS Better description and more terms from Ralf Stephan, Nov 03 2002 Corrected by T. D. Noe, Aug 25 2004 Offset corrected to 1 by M. F. Hasler, Feb 02 2016 STATUS approved

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Last modified January 29 04:57 EST 2020. Contains 331335 sequences. (Running on oeis4.)