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 A089244 Integer part of square root of the reciprocal of a prime number multiplied by 10 to the power of the integer part of the square root of the number. 0
 7, 5, 44, 37, 301, 277, 2425, 2294, 2085, 18569, 17960, 164398, 156173, 152498, 145864, 1373605, 1301889, 1280368, 12216944, 11867816, 11704114, 11250879, 109764259, 105999788, 101534616, 995037190, 985329278, 966736489, 957826285, 940720868, 8873565094, 8737040566 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS The sum of the reciprocals = 0.40100980056022072540219852776239... . Converges rapidly. LINKS Table of n, a(n) for n=2..33. FORMULA a(n) = floor( sqrt(1/x)*10^(floor(sqrt(x))) ), where x = prime(n). MATHEMATICA a[n_] := Module[{r = Sqrt[Prime[n]], ip, fp}, ip = Floor[r]; fp = r - ip; Floor[10^ip/r]]; Array[a, 40] (* Amiram Eldar, Jun 26 2024 *) PROG (PARI) rootrecipp(n) = { my(sr=0, r, ip, fp, y); forprime(x=2, n, r =sqrt(x); ip=floor(r); fp=r-ip; y=floor((1/r)*10^ip); print1(y", "); sr = sr + 1.0/y; ); print(); print(sr) } CROSSREFS Sequence in context: A146382 A163742 A202130 * A063003 A038271 A329008 Adjacent sequences: A089241 A089242 A089243 * A089245 A089246 A089247 KEYWORD easy,nonn AUTHOR Cino Hilliard, Dec 11 2003 EXTENSIONS More terms from Amiram Eldar, Jun 26 2024 STATUS approved

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Last modified August 8 15:25 EDT 2024. Contains 375022 sequences. (Running on oeis4.)