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%I #19 Feb 12 2021 17:43:42
%S 0,1,2,3,5,8,10,11,12,14,17,20,21,23,26,30,32,35,41,44,49,50,53,58,62,
%T 67,71,76,80,85,94,100,101,102,104,107,110,111,113,116,120,122,125,
%U 131,134,139,140,143,148,152,157,161,166,170,175,184,193,200,201,203,206
%N Numbers k such that sum of digits of k is a Fibonacci number.
%C The subsequence of primes begins: 2, 3, 5, 11, 17, 23, 41, 53, 67, 71, 101, 107, 113, 131, 139, 157, 193, 229, 233, 251 ... - _Dario Piazzalunga_, Jan 03 2013
%C The subsequence of Fibonacci numbers begins: 0, 1, 2, 3, 5, 8, 21, 233, ... (no more up to 100000). - _Dario Piazzalunga_, Jan 03 2013
%H Alois P. Heinz, <a href="/A028840/b028840.txt">Table of n, a(n) for n = 1..10000</a>
%p isA000045 := proc(n)
%p local i,f;
%p for i from 0 do
%p f := combinat[fibonacci](i) ;
%p if f = n then
%p return true;
%p elif f > n then
%p return false;
%p end if;
%p end do:
%p end proc:
%p isA028840 := proc(n)
%p isA000045(A007953(n)) ;
%p end proc:
%p for n from 0 to 1000 do
%p if isA028840(n) then
%p printf("%d,",n);
%p end if;
%p end do: # _R. J. Mathar_, Apr 17 2013
%p # second Maple program:
%p q:= proc(n) option remember; (t->
%p issqr(t+4) or issqr(t-4))(5*n^2)
%p end:
%p a:= proc(n) option remember; local k; for k from
%p `if`(n=1, 0, 1+a(n-1)) while not q(
%p add(i, i=convert(k, base, 10))) do od; k
%p end:
%p seq(a(n), n=1..66); # _Alois P. Heinz_, Jan 28 2020
%t f = Union[Fibonacci[Range[0, 8]]]; t = {}; n = 0; While[c = Total[IntegerDigits[n]]; c < f[[-1]], If[MemberQ[f, c], AppendTo[t, n]]; n++]; t (* _T. D. Noe_, Jan 03 2013 *)
%Y Cf. A000045, A007953, A028841, A028890.
%K nonn,base,easy
%O 1,3
%A _N. J. A. Sloane_
%E More terms from _Erich Friedman_
%E 0 inserted by _Dario Piazzalunga_, Jan 03 2013
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