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 A055461 Square decrescendo subsequences: triangle T(n,k) = (n-k)^2, n >= 1, 0 <= k < n. 6
 1, 4, 1, 9, 4, 1, 16, 9, 4, 1, 25, 16, 9, 4, 1, 36, 25, 16, 9, 4, 1, 49, 36, 25, 16, 9, 4, 1, 64, 49, 36, 25, 16, 9, 4, 1, 81, 64, 49, 36, 25, 16, 9, 4, 1, 100, 81, 64, 49, 36, 25, 16, 9, 4, 1, 121, 100, 81, 64, 49, 36, 25, 16, 9, 4, 1, 144, 121, 100, 81, 64, 49, 36, 25, 16, 9, 4, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row sums are A000330. - Michel Marcus, Dec 31 2012 Alternating row sums are A000217. - Omar E. Pol, Jan 24 2014 LINKS Robert Israel, Table of n, a(n) for n = 1..10011 (rows 1 to 141, flattened) FORMULA a(n) = A004736(n)^2 G.f. as triangle: x*(1+x)/((1-x*y)*(1-x)^3). - Robert Israel, Jan 18 2018 EXAMPLE 1; 4 1; 9 4 1; 16 9 4 1; etc. From Omar E. Pol, Jan 26 2014: (Start) Triangle begins: 1; 4,    1; 9,    4,  1; 16,   9,  4,  1; 25,  16,  9,  4,  1; 36,  25, 16,  9,  4,  1; 49,  36, 25, 16,  9,  4,  1; 64,  49, 36, 25, 16,  9,  4,  1; 81,  64, 49, 36, 25, 16,  9,  4,  1; 100, 81, 64, 49, 36, 25, 16,  9,  4,  1; ... For n = 7 the row sum is 49 + 36 + 25 + 16 + 9 + 4 + 1 = A000330(7) = 140. The alternating row sum is 49 - 36 + 25 - 16 + 9 - 4 + 1 = A000217(7) = 28. (End) MAPLE for n from 1 to 10 do   seq((n-k)^2, k=0..n-1) od; # Robert Israel, Jan 18 2018 CROSSREFS Sequence in context: A261981 A153265 A085691 * A324999 A104796 A132020 Adjacent sequences:  A055458 A055459 A055460 * A055462 A055463 A055464 KEYWORD easy,nonn,tabl AUTHOR Henry Bottomley, Jun 26 2000 STATUS approved

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Last modified October 19 02:41 EDT 2019. Contains 328211 sequences. (Running on oeis4.)