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 A007961 n written in base where place values are positive squares. 8
 1, 2, 3, 10, 11, 12, 13, 20, 100, 101, 102, 103, 110, 111, 112, 1000, 1001, 1002, 1003, 1010, 1011, 1012, 1013, 1020, 10000, 10001, 10002, 10003, 10010, 10011, 10012, 10013, 10020, 10100, 10101, 100000, 100001, 100002, 100003, 100010, 100011 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS For n>1: A000196(n) = number of digits of a(n); A190321(n) = number of nonzero digits of a(n); A053610(n) = sum of digits of a(n). [Reinhard Zumkeller, May 08 2011] LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 F. Smarandache, Only Problems, Not Solutions!. MAPLE A007961 := proc(n)     local k, nrem, L, b, d;     k := floor(sqrt(n)) ;     nrem := n ;     L := [] ;     for b from k to 1 by -1 do         d := floor(nrem/b^2) ;         L := [d, op(L)] ;         nrem := nrem -d*b^2 ;     end do:     add( op(i, L)*10^(i-1), i=1..nops(L)) ; end proc: # R. J. Mathar, Jul 25 2015 PROG (Haskell) import Data.Char (intToDigit) a007961 :: Integer -> Integer a007961 n = read \$ map intToDigit \$   t n \$ reverse \$ takeWhile (<= n) \$ tail a000290_list where     t _ []          = []     t m (x:xs)         | x > m     = 0 : t m xs         | otherwise = (fromInteger m') : t r xs         where (m', r) = divMod m x -- Reinhard Zumkeller, May 08 2011 CROSSREFS Cf. A000290, A000433. Sequence in context: A102859 A069967 A061909 * A212067 A060811 A146327 Adjacent sequences:  A007958 A007959 A007960 * A007962 A007963 A007964 KEYWORD nonn,base AUTHOR R. Muller STATUS approved

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