The OEIS is supported by the many generous donors to the OEIS Foundation.

 Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”). Other ways to Give
 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A322643 Number of times the digit 2 appears in the first 10^n decimal digits of sqrt(2), sometimes called Pythagoras's constant, counting after the decimal point. 10
 2, 8, 109, 1004, 9876, 100436, 1000208, 9998091, 99995645, 999987069 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS It is not known if sqrt(2) is normal, but the distribution of decimal digits found for the first 10^n digits of sqrt(2) shows no statistically significant departure from a uniform distribution. LINKS Eric Weisstein's World of Mathematics, Pythagoras's Constant Digits. MAPLE a:=proc(n) local digits, SQRT2, C, i; digits:=10^n+100; SQRT2:=convert(frac(evalf[digits](sqrt(2))), string)[2..digits-99]; C:=0; for i from 1 to length(SQRT2) do if SQRT2[i]="2" then C:=C+1; fi; od; return(C); end; MATHEMATICA Table[DigitCount[IntegerPart[(Sqrt[2]-1)*10^10^n], 10, 2], {n, 1, 10}] (* Robert Price, Mar 29 2019 *) CROSSREFS Cf. A002193, A099293, A322641, A322642, A322644, A322645, A322646, A322647, A322648, A322649, A322650. Sequence in context: A256398 A008926 A136468 * A178171 A132523 A012554 Adjacent sequences: A322640 A322641 A322642 * A322644 A322645 A322646 KEYWORD nonn,base,more AUTHOR Martin Renner, Dec 21 2018 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 8 19:12 EST 2022. Contains 358698 sequences. (Running on oeis4.)