The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation. Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A128546 Inrepfigit (INverse REPetitive FIbonacci-like diGIT) numbers (or Htiek numbers). 3
 17, 21, 25, 42, 63, 84, 143, 286, 2355, 5821, 6618, 11709, 12482, 33747, 39571, 129109, 466957, 1162248, 1565166, 1968084, 3636638, 3853951, 4898376, 6065280, 13443745, 13933175, 17118698, 22421197, 24153462377 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This sequence is similar to A007629 (Keith numbers). It consists of the numbers n>9 with the following property: n is a term of the sequence S whose first k terms are the k digits of n (with the first term equal to the units digit) and with S(n+1)=sum of the k previous terms. LINKS EXAMPLE 42 is in the sequence because the terms of the sequence it creates are 2, 4, 6, 10, 16, 26, 42, ... MATHEMATICA iKeithQ[n_Integer] := Module[{b = Reverse[IntegerDigits[n]], s, k = 0}, s = Total[b]; While[s < n, AppendTo[b, s]; k++; s = 2*s - b[[k]]]; s == n]; Select[Range[10, 100000], iKeithQ] (* T. D. Noe, Mar 15 2011 *) PROG Here is a (messy) C++ code which finds the terms of the sequence below 100000000 #include int main() { int k2; for ( int k = 10 ; k < 100000000 ; k++ ) { k2 = k; int array ; for ( int i = 0 ; i <= 8; i++ ) { array[i] = k2 % 10; k2 /= 10; } bool c = true; int check=8; for ( int i = 0; i <=8; i++ ) { if ((array[8-i]==0)&&c) check--; else c=false; } bool b = false; int n = 0; while ( n <= k && !b ) { n = 0; for ( int i = 0; i <= check; i++ ) n += array[i]; if ( n == k ) b = true; for ( int i = 0 ; i < check ; i++ ) array[i] = array[i+1]; array[check] = n; } if ( b ) printf("%d ", k); } return 0; } CROSSREFS Cf. A007629. Cf. A097060 (reverse of these numbers). Sequence in context: A166875 A282109 A307863 * A188200 A060875 A259555 Adjacent sequences:  A128543 A128544 A128545 * A128547 A128548 A128549 KEYWORD base,nonn AUTHOR Pierre Karpman (pierre.karpman(AT)laposte.net), Oct 23 2007 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 18 06:27 EDT 2021. Contains 348065 sequences. (Running on oeis4.)