A007961 n written in base where place values are positive squares.

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

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: A061909 A345358 A337110 * A212067 A060811 A146327

Adjacent sequences: A007958 A007959 A007960 * A007962 A007963 A007964

Keyword

nonn,base

Author

R. Muller

Status

approved