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 A061384 Numbers n such that sum of digits = number of digits. 11
 1, 11, 20, 102, 111, 120, 201, 210, 300, 1003, 1012, 1021, 1030, 1102, 1111, 1120, 1201, 1210, 1300, 2002, 2011, 2020, 2101, 2110, 2200, 3001, 3010, 3100, 4000, 10004, 10013, 10022, 10031, 10040, 10103, 10112, 10121, 10130, 10202, 10211 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Number of d-digit entries is A071976(d). - Robert Israel, Apr 06 2016 Equivalently, numbers n > 0 for which the arithmetic mean of the digits equals 1. - M. F. Hasler, Dec 07 2018 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 FORMULA {n > 0 | A007953(n) = A055642(n)}. - M. F. Hasler, Dec 07 2018 EXAMPLE 120 is a term as the arithmetic mean of the digits is (1+2+0)/3 = 1. MAPLE Q:= proc(n, s) option remember; # n-digit integers with digit sum s if s = 0 then [] elif s = 1 then [10^(n-1)] elif n = 1 then    if s <= 9 then [s]    else []    fi else   map(op, [seq(map(t -> 10*t+i, procname(n-1, s-i)), i=0..min(9, s-1))]) fi end proc: map(op, [seq(sort(Q(n, n)), n=1..5)]); # Robert Israel, Apr 06 2016 MATHEMATICA Select[Range[15000], Total[IntegerDigits[#]] == IntegerLength[#]&] (* Harvey P. Dale, Jan 08 2011 *) PROG (MAGMA) [ n: n in [1..10215] | &+Intseq(n) eq #Intseq(n) ]; // Bruno Berselli, Jun 30 2011 (PARI) isok(n) = (sumdigits(n)/#Str(n) == 1); \\ Michel Marcus, Mar 28 2016 (PARI) is_A061384(n)={sumdigits(n)==logint(n+!n, 10)+1} \\ M. F. Hasler, Dec 07 2018 (PARI) A061384_row(n)={my(L=List(), u=vector(n, i, i==1), d); forvec(v=vector(n+1, i, [if(i>n, n, 1), if(i>1, n, 1)]), vecmax(d=v[^1]-v[^-1]+u)<10 && listput(L, fromdigits(d)), 1); Vec(L)} \\ Return the list of all n-digit terms. - M. F. Hasler, Dec 07 2018 CROSSREFS Totally balanced subset: A071154. Cf. also A061383-A061388, A061423-A061425. Cf. A071976. Cf. A007953 (sum of digits), A055642 (number of digits). Sequence in context: A180113 A198310 A085187 * A071154 A071161 A125886 Adjacent sequences:  A061381 A061382 A061383 * A061385 A061386 A061387 KEYWORD nonn,base,easy,changed AUTHOR Amarnath Murthy, May 03 2001 EXTENSIONS More terms from Erich Friedman, May 08 2001 STATUS approved

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Last modified December 18 16:21 EST 2018. Contains 318229 sequences. (Running on oeis4.)