A068809 Squares with strictly increasing sum of digits.

1, 4, 9, 49, 169, 289, 1849, 3969, 6889, 27889, 69696, 97969, 499849, 698896, 2778889, 4999696, 9696996, 19998784, 46689889, 66699889, 79869969, 277788889, 478996996, 876988996, 1749999889, 5599977889, 7998976969, 8998988769, 17999978896

Offset: 1

Author

Amarnath Murthy, Mar 06 2002

Keywords

• base
• nonn

Links

• Giovanni Resta, Table of n, a(n) for n = 1..80 (first 57 terms from Kevin Buzzard)

Crossrefs

Cf. A068947, A068948, A068949, A068950, A068952, A069324.

Programs

Maple

A007953 := proc(n) option remember: return add(d, d=convert(n, base, 10)): end: A068947 := proc(n) option remember: local k, p: if(n=1)then return 1: fi: k:=procname(n-1): p:=A007953(k^2): do k:=k+1: if(A007953(k^2)>p)then return k: fi: od: end: seq(A068947(n)^2, n=1..20); # Nathaniel Johnston, May 04 2011

Mathematica

t = {}; s = 0; Do[If[(x = Total[IntegerDigits[y = n^2]]) > s, AppendTo[t, y]; s = x], {n, 150000}]; t (* Jayanta Basu, Aug 06 2013 *)

Extensions

More terms from Francois Jooste (phukraut(AT)hotmail.com), Mar 15 2002