A116281 - OEIS

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A116281

Numbers k such that k*(k+5) gives the concatenation of two numbers m and m-1.

5

39, 57, 32262231, 67737765, 79321055, 3341093417798787499092, 3861488851737861033960, 4747922651210186579786, 5252077348789813420210, 6138511148262138966036, 6658906582201212500904, 7232275368591793618230

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..12.

EXAMPLE

79321055 * 79321060 = 62918301//62918300, where // denotes concatenation.

CROSSREFS

Cf. A028557, A116112, A116276, A116280, A116282, A116289.

Sequence in context: A009633 A327586 A156333 * A168530 A253436 A253429

Adjacent sequences: A116278 A116279 A116280 * A116282 A116283 A116284

KEYWORD

nonn,base

AUTHOR

Giovanni Resta, Feb 06 2006

STATUS

approved