Numbers n=2*k-1 where Sum_{j=1..k} (-1)^(j+1) * d(2*j-1) achieves a new record, with d(n) = number of divisors of n (A000005).
A318737
Numbers n=2*k-1 where Sum_{j=1..k} (-1)^(j+1) * d(2*j-1) achieves a new record, with d(n) = number of divisors of n (A000005).
Terms
- a(0) =1a(1) =9a(2) =25a(3) =49a(4) =85a(5) =133a(6) =169a(7) =225a(8) =445a(9) =845a(10) =973a(11) =1125a(12) =2205a(13) =2209a(14) =2469a(15) =2829a(16) =7929a(17) =9429a(18) =9945a(19) =23569a(20) =24073a(21) =24645a(22) =26145a(23) =40425a(24) =68153a(25) =71289a(26) =72413a(27) =89517a(28) =112233a(29) =112245
External references
- oeis: A318737