# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a373964 Showing 1-1 of 1 %I A373964 #9 Jun 24 2024 08:47:22 %S A373964 0,0,0,1,5,15,35,70,127,221,396,781,1716,4005,9390,21421,47107,100283, %T A373964 208982,432197,898064,1889152,4028036,8671852,18739049,40434205, %U A373964 86861995,185669195,395358538,840341619,1786426005,3803164340,8111872645,17329007156 %N A373964 Number of compositions of 6*n-4 into parts 5 and 6. %H A373964 Index entries for linear recurrences with constant coefficients, signature (6,-15,20,-15,7,-1). %F A373964 a(n) = A017837(6*n-4). %F A373964 a(n) = Sum_{k=0..floor(n/5)} binomial(n+k,n-4-5*k). %F A373964 a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 7*a(n-5) - a(n-6). %F A373964 G.f.: x^4*(1-x)/((1-x)^6 - x^5). %F A373964 a(n) = A369794(n+1) - A369794(n). %o A373964 (PARI) a(n) = sum(k=0, n\5, binomial(n+k, n-4-5*k)); %Y A373964 Cf. A107025, A369794, A373961, A373962, A373963. %Y A373964 Cf. A017837. %K A373964 nonn,easy %O A373964 1,5 %A A373964 _Seiichi Manyama_, Jun 24 2024 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE