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A244733 Semiprimes sp such that sp plus its digit sum is a perfect square. 2
38, 86, 161, 614, 662, 998, 1145, 1355, 1829, 2189, 2483, 4607, 5027, 5315, 6377, 7199, 8258, 11435, 13214, 15611, 17933, 19574, 20153, 21305, 21878, 24014, 26867, 30599, 32738, 34199, 36077, 38387, 38777, 40778, 42422, 46211, 51509, 52874, 56618, 58541, 59987 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

K. D. Bajpai, Table of n, a(n) for n = 1..1150

EXAMPLE

86 is in the sequence because 86 = 2* 43, which is semiprime. Also, 86 + (8 + 6) = 100 = 10^2.

614 is in the sequence because 614 = 2* 307, which is semiprime. Also, 614 + (6 + 1 + 4) = 625 = 25^2.

MATHEMATICA

Select[Range[50000], PrimeOmega[#] == 2 && IntegerQ[Sqrt[# + Apply[Plus, IntegerDigits[#]]]] &]

CROSSREFS

Cf. A007953, A028839, A048519, A107288, A244863.

Sequence in context: A044024 A133529 A211498 * A044176 A044557 A014716

Adjacent sequences:  A244730 A244731 A244732 * A244734 A244735 A244736

KEYWORD

nonn,base

AUTHOR

K. D. Bajpai, Jul 12 2014

STATUS

approved

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Last modified May 7 18:29 EDT 2021. Contains 343652 sequences. (Running on oeis4.)