A053240 - OEIS

A053240

n for which values not equal to 2 occur in the expansion of A053238.

5, 20, 21, 29, 34, 49, 50, 56, 57, 65, 70, 79, 80, 94, 99, 108, 109, 123, 132, 133, 145, 146, 154, 155, 170, 171, 177, 178, 198, 200, 201, 227, 230, 231, 239, 244, 253, 254, 259, 260, 274, 277, 278, 280, 289, 290, 304, 307, 308, 310, 327, 332, 340, 341, 347

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OFFSET

1,1

LINKS

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

MAPLE

with(numtheory): f := [seq( `if`((sigma(i) > sigma(i+1)), i, print( )), i=1..5000)];

seq( `if`(f[i+1] - f[i] <> 2, i, print( )), i=1..1000);

PROG

(Haskell)

import Data.List (findIndices)

a053240 n = a053240_list !! (n-1)