Numbers n=2*k-1 where Sum_{j=1..k} (-1)^(j+1) * d(2*j-1) achieves a new negative record, with d(n) = number of divisors of n (A000005).
A318738
Numbers n=2*k-1 where Sum_{j=1..k} (-1)^(j+1) * d(2*j-1) achieves a new negative record, with d(n) = number of divisors of n (A000005).
Terms
- a(0) =3a(1) =15a(2) =39a(3) =63a(4) =99a(5) =259a(6) =319a(7) =403a(8) =675a(9) =679a(10) =943a(11) =1615a(12) =1779a(13) =2919a(14) =4899a(15) =5775a(16) =7399a(17) =7407a(18) =13475a(19) =13479a(20) =25635a(21) =29835a(22) =29839a(23) =44955a(24) =78463a(25) =78475a(26) =108927a(27) =108931a(28) =126819a(29) =136959
External references
- oeis: A318738