A249043 a(1) = 42; a(n+1) = a(n) + sum of decimal digits of a(n).

42, 48, 60, 66, 78, 93, 105, 111, 114, 120, 123, 129, 141, 147, 159, 174, 186, 201, 204, 210, 213, 219, 231, 237, 249, 264, 276, 291, 303, 309, 321, 327, 339, 354, 366, 381, 393, 408, 420, 426, 438, 453, 465, 480, 492, 507, 519, 534, 546, 561, 573, 588, 609, 624, 636

Offset: 1

Author

N. J. A. Sloane, Oct 30 2014

Keywords

• easy
• nonn
• base

References

• D. R. Kaprekar, The Mathematics of the New Self Numbers, Privately Printed, 311 Devlali Camp, Devlali, India, 1963.

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
• D. R. Kaprekar, The Mathematics of the New Self Numbers [annotated and scanned]
• Index entries for Colombian or self numbers and related sequences

Crossrefs

Cf. A004207, A016052, A007618, A006507, A016052, A036228.

Cf. A007953, A062028.

Programs

Haskell

a249043 n = a249043_list !! (n-1)
a249043_list = iterate a062028 42
-- Reinhard Zumkeller, Oct 31 2014

Formula

a(n+1) = A062028(a(n)). - Reinhard Zumkeller, Oct 31 2014