login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A329779
Numbers that are either odd or are congruent to {+-4, +-6, +-8, +-10} (mod 32).
5
1, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 21, 22, 23, 24, 25, 26, 27, 28, 29, 31, 33, 35, 36, 37, 38, 39, 40, 41, 42, 43, 45, 47, 49, 51, 53, 54, 55, 56, 57, 58, 59, 60, 61, 63, 65, 67, 68, 69, 70, 71, 72, 73, 74, 75, 77, 79, 81, 83, 85, 86, 87, 88
OFFSET
1,2
LINKS
G. E. Andrews, Further Problems on Partitions, Amer. Math. Monthly 94 (1987), no. 5, 437-439.
Index entries for linear recurrences with constant coefficients, signature (2,-1,0,0,0,0,0,-1,2,-1,0,0,0,0,0,-1,2,-1).
FORMULA
From Colin Barker, Dec 01 2019: (Start)
G.f.: x*(1 + x)*(1 - x^2 + x^3 - x^4 + x^5 - x^6 + x^7 + x^9 - x^10 + x^11 - x^12 + x^13 - x^14 + x^16) / ((1 - x)^2*(1 - x + x^2)*(1 + x + x^2)*(1 - x^2 + x^4)*(1 - x^4 + x^8)).
a(n) = 2*a(n-1) - a(n-2) - a(n-8) + 2*a(n-9) - a(n-10) - a(n-16) + 2*a(n-17) - a(n-18) for n>18.
(End)
MAPLE
lis1:=[4, 6, 8, 10];
f:=proc(n, M, lis) local i;
if member( n mod M, lis) or member( -n mod M, lis) then 1 else 0; fi; end;
a:=[];
for n from 1 to 200 do
if (n mod 2) = 1 or f(n, 32, lis1) = 1 then a:=[op(a), n]; fi; od:
a;
MATHEMATICA
okQ[n_] := OddQ[n] || AnyTrue[{4, 6, 8, 10, 22, 24, 26, 28}, Mod[n, 32] == #&];
Select[Range[100], okQ] (* Jean-François Alcover, Mar 09 2023 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Nov 29 2019
STATUS
approved