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 A078705 Integer part of the square root of sigma(n). 2
 1, 1, 2, 2, 2, 3, 2, 3, 3, 4, 3, 5, 3, 4, 4, 5, 4, 6, 4, 6, 5, 6, 4, 7, 5, 6, 6, 7, 5, 8, 5, 7, 6, 7, 6, 9, 6, 7, 7, 9, 6, 9, 6, 9, 8, 8, 6, 11, 7, 9, 8, 9, 7, 10, 8, 10, 8, 9, 7, 12, 7, 9, 10, 11, 9, 12, 8, 11, 9, 12, 8, 13, 8, 10, 11, 11, 9, 12, 8, 13, 11, 11, 9, 14, 10, 11, 10, 13, 9, 15, 10, 12, 11 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Antti Karttunen, Table of n, a(n) for n = 1..16384 FORMULA a(n) = A000196(A000203(n)). - Antti Karttunen, Nov 18 2017 MATHEMATICA Table[Floor[Sqrt[DivisorSigma[1, i]]], {i, 1, 100}] PROG (Scheme) (define (A078705 n) (A000196 (A000203 n))) ;; [For the implementations of A000196 and A000203, see under the respective entries]. - Antti Karttunen, Nov 18 2017 (PARI) a(n) = sqrtint(sigma(n)); \\ Michel Marcus, Nov 18 2017 CROSSREFS Cf. A000196, A000203. Sequence in context: A112310 A137734 A182210 * A050331 A259194 A194344 Adjacent sequences:  A078702 A078703 A078704 * A078706 A078707 A078708 KEYWORD easy,nonn,look AUTHOR Joseph L. Pe, Dec 18 2002 STATUS approved

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Last modified June 2 14:21 EDT 2020. Contains 334787 sequences. (Running on oeis4.)