A178241 Numbers n such that d(1)^p + d(2)^(p-1) +... + d(p)^1 is a square, where d(i), i=1..p, are the digits of n.

0, 1, 4, 9, 10, 13, 18, 20, 25, 30, 37, 40, 49, 50, 60, 70, 80, 90, 100, 103, 108, 112, 117, 124, 136, 148, 201, 208, 210, 217, 224, 238, 241, 253, 265, 277, 289, 309, 318, 325, 330, 346, 361, 375, 389, 400, 438, 441, 460, 478, 543, 568, 587, 609, 618, 625, 630, 664, 689, 739, 742, 778, 838, 841, 880, 900, 976, 1000

Offset

0,3

Comments

Numbers n such that A114570(n) is a perfect square.

Links

Table of n, a(n) for n=0..67.

Example

253 is in the sequence because 2^3 + 5^2 + 3 = 36 = 6^2.

Maple

with(numtheory):for n from 0 to 1000 do:l:=length(n):n0:=n:s1:=0:s2:=0:for
  m from 1 to l do:q:=n0:u:=irem(q, 10):v:=iquo(q, 10):n0:=v :s2:=s2+u^m:od:s20:=sqrt(s2):
  if s20=floor(s20)then printf(`%d, `, n):else fi:od:

Crossrefs

Sequence in context: A197039 A020672 A028837 * A028839 A141833 A140292

Adjacent sequences: A178238 A178239 A178240 * A178242 A178243 A178244

Keyword

nonn,base

Author

Michel Lagneau, Dec 20 2010

Status

approved