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A256083 Non-palindromic balanced numbers in base 3. 2
87, 96, 105, 137, 146, 155, 169, 178, 187, 264, 276, 312, 348, 380, 416, 452, 464, 508, 520, 556, 592, 741, 768, 795, 816, 831, 843, 858, 870, 885, 895, 906, 922, 933, 949, 960, 987, 991, 1014, 1018, 1041, 1045, 1055, 1077, 1082, 1104, 1109, 1131, 1141, 1145, 1168, 1172, 1195, 1199, 1226, 1237, 1253, 1264, 1280, 1291, 1301 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Here a number is called balanced if the sum of digits weighted by their arithmetic distance from the "center" is zero.

This is the base-3 variant of the decimal version A256075 invented by Eric Angelini.

All balanced numbers with less than 4 digits are palindromic, and since there is no digit 3 in base 3, there cannot be a term in this sequence with 4 base-3 digits, where weights are (-3/2, -1/2, 1/2, 3/2).

LINKS

Table of n, a(n) for n=1..61.

EXAMPLE

a(4) = 137 = 12002[3] is balanced because 1*2 + 2*1 = 0*1 + 2*2.

PROG

(PARI) is(n, b=3, d=digits(n, b), o=(#d+1)/2)=!(vector(#d, i, i-o)*d~)&&d!=Vecrev(d)

CROSSREFS

Cf. A256082 - A256089, A256075, A256080.

Sequence in context: A095583 A323414 A231403 * A038005 A305266 A046003

Adjacent sequences:  A256080 A256081 A256082 * A256084 A256085 A256086

KEYWORD

nonn,base

AUTHOR

M. F. Hasler, Mar 14 2015

STATUS

approved

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Last modified December 4 08:16 EST 2021. Contains 349479 sequences. (Running on oeis4.)