A031291 Position of n-th 4 in A007376.

4, 19, 39, 59, 70, 72, 74, 76, 78, 79, 80, 82, 84, 86, 88, 99, 119, 139, 159, 179, 204, 234, 264, 294, 311, 314, 317, 320, 323, 324, 326, 329, 332, 335, 338, 354, 384, 414, 444, 474, 504, 534, 564, 594, 611, 614, 617, 620, 623, 624

Offset: 1

Author

Clark Kimberling

Keywords

• nonn
• less
• base

Comments

A007376(a(n)) = 4.

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A193428; A031287, A031288, A031289, A031290, A031292, A031293, A031294, A031295, A031296.

Programs

Haskell

import Data.List (elemIndices)
a031291 n = a031291_list !! (n-1)
a031291_list = map (+ 1) $ elemIndices 4 a007376_list
-- Reinhard Zumkeller, Jul 28 2011