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A316481 Squares whose arithmetic mean of digits is 1 (i.e., the sum of digits equals the number of digits). 2
1, 1100401, 2220100, 100040004, 100100025, 100220121, 100400400, 101002500, 102030201, 102212100, 103002201, 104040000, 110250000, 121022001, 121220100, 123210000, 132020100, 144000000, 210221001, 225000000, 310112100, 324000000, 400040001, 400400100 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Each term's number of digits is in A056991 (Numbers with digital root 1, 4, 7, or 9). For every term k in A056991, this sequence contains at least one k-digit term, with the exception of k=4. (See A316480.)

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..10000 (first 1543 terms from Jon E. Schoenfield)

EXAMPLE

1049^2 = 1100401, a 7-digit number whose digit sum is 1+1+0+0+4+0+1 = 7, so 1100401 is a term.

MAPLE

P:=proc(n, h) local a; a:=convert(n^2, base, 10);

if convert(a, `+`)/nops(a)=h then n^2; fi; end:

seq(P(i, 1), i=1..20010); # Paolo P. Lava, Jul 13 2018

CROSSREFS

Cf. A056991, A069711, A316480.

Intersection of A000290 and A061384. - Michel Marcus, Jul 06 2018

Sequence in context: A268036 A184384 A086212 * A253619 A235221 A060087

Adjacent sequences:  A316478 A316479 A316480 * A316482 A316483 A316484

KEYWORD

nonn,base

AUTHOR

Jon E. Schoenfield, Jul 04 2018

STATUS

approved

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Last modified July 18 19:00 EDT 2019. Contains 325144 sequences. (Running on oeis4.)