A091012 - OEIS

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A091012

Numbers having exactly one divisor d such that for some x also d-x and d+x are divisors.

6, 15, 28, 40, 91, 153, 190, 220, 325, 496, 544, 561, 572, 627, 703, 861, 897, 935, 946, 1012, 1225, 1287, 1292, 1431, 1581, 1610, 1653, 1768, 1891, 2278, 2300, 2465, 2618, 2701, 2967, 3321, 3344, 3496, 3596, 3655, 3952, 4123, 4301, 4324, 4371

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

A091009(a(n)) = 1.

LINKS

Table of n, a(n) for n=1..45.

CROSSREFS

Cf. A091013, A091011.

Sequence in context: A242454 A161777 A117519 * A241988 A058008 A094142

Adjacent sequences: A091009 A091010 A091011 * A091013 A091014 A091015

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Dec 13 2003

STATUS

approved