A027920 Least k such that 2nd elementary symmetric function of {1,2,...,k} >= 4th elementary symmetric function of {1,2,...,n}.

3, 6, 10, 15, 20, 26, 33, 40, 49, 58, 68, 78, 90, 102, 115, 129, 143, 158, 174, 191, 208, 227, 246, 265, 286, 307, 329, 352, 376, 400, 425, 451, 477, 505, 533, 562, 591, 622, 653, 685, 717, 751, 785, 820, 856, 892, 929, 967, 1006, 1046, 1086, 1127, 1169, 1211

Offset: 4

Author

Clark Kimberling

Keywords

• nonn

Crossrefs

Cf. A000914, A000915.

Formula

a(n) = min{k: A000914(k) >= A000915(n-3)}. - Sean A. Irvine, Dec 10 2019

Extensions

More terms from Sean A. Irvine, Dec 10 2019