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A081990 Numbers k such that both k+1 and (product of digits of k) + 1 are squares. 3
3, 8, 24, 35, 168, 528, 624, 783, 1443, 3843, 5183, 7568, 8835, 12543, 13224, 15128, 17423, 24335, 26243, 27224, 41615, 47523, 75624, 87615, 92415, 118335, 128163, 135423, 172224, 213443, 225624, 262143, 265224, 274575, 338723, 345743, 374543 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..37.

EXAMPLE

168 belongs to this sequence as both 1*6*8 + 1 = 49 and 168 + 1 = 169 are squares.

CROSSREFS

Cf. A081989.

Sequence in context: A065083 A280190 A037450 * A084920 A323278 A026556

Adjacent sequences:  A081987 A081988 A081989 * A081991 A081992 A081993

KEYWORD

base,easy,nonn

AUTHOR

Amarnath Murthy, Apr 04 2003

EXTENSIONS

Corrected and extended by Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 06 2003

STATUS

approved

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Last modified August 6 17:06 EDT 2020. Contains 336255 sequences. (Running on oeis4.)