A053241 Numbers n such that A053238(n) = 2.

1, 2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 22, 23, 24, 25, 26, 27, 28, 30, 31, 32, 33, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 51, 52, 53, 54, 55, 58, 59, 60, 61, 62, 63, 64, 66, 67, 68, 69, 71, 72, 73, 74, 75, 76, 77, 78, 81, 82, 83, 84, 85

Offset

1,2

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..100);

Prog

(Haskell)
import Data.List (elemIndices)
a053241 n = a053241_list !! (n-1)
a053241_list = map (+ 1) $ elemIndices 2 a053238_list
-- Reinhard Zumkeller, Oct 16 2011

Crossrefs

Cf. A000203, A053226, A053238, A053239, A053240 (complement), A053242, A053243, A053244, A053245.

Sequence in context: A004724 A099260 A231237 * A340288 A132329 A230313

Adjacent sequences: A053238 A053239 A053240 * A053242 A053243 A053244

Keyword

nonn

Author

Asher Auel, Jan 10 2000

Status

approved