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 A331071 a(n) = Sum_{k <= n} r_2(k)^2*d(k+1), where r_2 = A004018, d = A000005. 3
 1, 33, 65, 65, 97, 353, 353, 353, 401, 465, 593, 593, 593, 849, 849, 849, 881, 1265, 1297, 1297, 1553, 1553, 1553, 1553, 1553, 2129, 2385, 2385, 2385, 2897, 2897, 2897, 2961, 2961, 3217, 3217, 3249, 3505, 3505, 3505, 3633, 4145, 4145, 4145, 4145, 4401, 4401, 4401, 4401, 4497, 5073, 5073, 5201, 5713, 5713 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Partial sums of A330574. REFERENCES Steven R. Finch, Mathematical Constants II, Encyclopedia of Mathematics and Its Applications, Cambridge University Press, Cambridge, 2018, p. 163. LINKS Amiram Eldar, Table of n, a(n) for n = 0..10000 Karl-Heinz Indlekofer, Eine asymptotische Formel in der Zahlentheorie, (German) Arch. Math. (Basel) 23 (1972), 619-624. MR0318080 (47 #6629). FORMULA a(n) ~ c * n * log(n)^2, where c is a constant. - Amiram Eldar, Mar 05 2020 MATHEMATICA Accumulate @ Table[SquaresR[2, n]^2 * DivisorSigma[0, n+1], {n, 0, 50}] (* Amiram Eldar, Mar 05 2020 *) CROSSREFS Cf. A000005, A004018, A330574. Sequence in context: A053179 A183347 A116350 * A062059 A285317 A198592 Adjacent sequences: A331068 A331069 A331070 * A331072 A331073 A331074 KEYWORD nonn AUTHOR N. J. A. Sloane, Jan 10 2020 STATUS approved

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Last modified December 10 15:23 EST 2023. Contains 367713 sequences. (Running on oeis4.)