

A226916


Number of (17,11)reverse multiples with n digits.


7



0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 2, 1, 2, 2, 3, 3, 5, 4, 7, 6, 10, 9, 15, 13, 22, 19, 32, 28, 47, 41, 69, 60, 101, 88, 148, 129, 217, 189, 318, 277, 466, 406, 683, 595, 1001, 872, 1467, 1278, 2150, 1873, 3151, 2745, 4618, 4023, 6768, 5896, 9919, 8641, 14537, 12664, 21305, 18560, 31224, 27201, 45761
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OFFSET

0,11


COMMENTS

Comment from Emeric Deutsch, Aug 21 2016 (Start):
Given an increasing sequence of positive integers S = {a0, a1, a2, ... }, let
F(x) = x^{a0} + x^{a1} + x^{a2} + ... .
Then the g. f. for the number of palindromic compositions of n with parts in S is (see Hoggatt and Bicknell, Fibonacci Quarterly, 13(4), 1975, 350  356):
(1 + F(x))/(1  F(x^2))
Playing with this, I have found easily that
1. number of palindromic compositions of n into {3,4,5,...} = A226916(n+4);
2. number of palindromic compositions of n into {1,4,7,10,13,...} = A226916(n+6);
3. number of palindromic compositions of n into {1,4} = A226517(n+10);
4. number of palindromic compositions of n into {1,5} = A226516(n+11).
(End)


LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000
N. J. A. Sloane, 2178 And All That, Fib. Quart., 52 (2014), 99120.


FORMULA

G.f.: x^4*(1x^2+x^3+x^4)/(1x^2x^6).


MATHEMATICA

CoefficientList[Series[x^4 (1  x^2 + x^3 + x^4) / (1  x^2  x^6), {x, 0, 70}], x] (* Vincenzo Librandi, Jul 16 2013 *)


CROSSREFS

Cf. A214927, A226516, A226517.
Sequence in context: A161052 A161256 A161281 * A003113 A225502 A152227
Adjacent sequences: A226913 A226914 A226915 * A226917 A226918 A226919


KEYWORD

nonn,base


AUTHOR

N. J. A. Sloane, Jun 24 2013


STATUS

approved



