OFFSET
1,2
COMMENTS
Contains numbers of the form 10^k, k >= 0 so the sequence is infinite. - David A. Corneth, Oct 30 2018
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..500
EXAMPLE
3103 = C(22, 3) + C(22, 1) + C(22, 0) + C(22, 3).
C(k, 1) + C(k, 1) + C(k, 1) + C(k, 0) + C(k, 0) + C(k, 0) = 3k + 3 so all 6-digit numbers with 3 ones and 3 zeros are in the sequence. - David A. Corneth, Oct 30 2018
MATHEMATICA
ok[n_] := Block[{d = IntegerDigits@n, k=1, v, x}, If[ Max@d <= 3, False =!= Reduce[ Total@ Binomial[x, d] == n && x>0, x, Integers], While[(v = Total@ Binomial[k, d]) < n, k++]; v == n]]; Select[ Range[10^5], ok] (* Giovanni Resta, Oct 30 2018 *)
PROG
(PARI) is(n) = my(d = digits(n)); for(i = 1, n, s = sum(j = 1, #d, binomial(i, d[j])); if(s >= n, return(s == n))) \\ David A. Corneth, Oct 30 2018
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Erich Friedman, Jun 27 2000
EXTENSIONS
a(31)-a(41) from Giovanni Resta, Oct 30 2018
STATUS
approved