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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
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.
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
KEYWORD
nonn,base
AUTHOR
Michel Lagneau, Dec 20 2010
STATUS
approved