Number of nondecreasing arrangements of n numbers x(i) in -(n+6)..(n+6) with the sum of sign(x(i))*2^|x(i)| zero.
A187987
Number of nondecreasing arrangements of n numbers x(i) in -(n+6)..(n+6) with the sum of sign(x(i))*2^|x(i)| zero.
Terms
- a(0) =0a(1) =8a(2) =17a(3) =72a(4) =267a(5) =915a(6) =3407a(7) =12148a(8) =43820a(9) =158361a(10) =570132a(11) =2058621a(12) =7429283a(13) =26823311a(14) =96904923a(15) =350182773a(16) =1266059030a(17) =4579170527a(18) =16568732508a(19) =59974168593a(20) =217170088270a(21) =786671363225
External references
- oeis: A187987