OFFSET
1,2
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 24*a(n-1) - 218*a(n-2) + 1009*a(n-3) - 2623*a(n-4) + 3513*a(n-5) - 142*a(n-6) - 7707*a(n-7) + 11632*a(n-8) - 4443*a(n-9) - 6736*a(n-10) + 9655*a(n-11) - 3714*a(n-12) - 1529*a(n-13) + 1550*a(n-14) - 597*a(n-15) + 1041*a(n-16) + 195*a(n-17) - 150*a(n-18) + 8*a(n-19) + a(n-20) for n > 20. - Andrew Howroyd, Oct 02 2017
Empirical: x *(-1 -15*x +69*x^2 +140*x^3 -1117*x^4 +1696*x^5 +186*x^6 -1351*x^7 -1715*x^8 +3376*x^9 -52*x^10 -1829*x^11 +905*x^12 -1748*x^13 +446*x^14 -241*x^15 -72*x^16 +35*x^17 +7*x^18 +x^19) / ( (x^2+2*x-1) *(x^6 -7*x^5 +x^4 +6*x^3 -11*x^2 +7*x -1) *(x^12 +13*x^11 -71*x^10 +7*x^9 -113*x^8 +22*x^7 +222*x^6 -210*x^5 -19*x^4 +97*x^3 -59*x^2 +15*x -1) ). - R. J. Mathar, Jun 07 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved