

A324649


Numbers n such that A318458(n) (bitwiseAND of n and sigma(n)n) is equal to n.


7



6, 20, 28, 36, 66, 72, 88, 100, 104, 114, 132, 150, 240, 258, 264, 272, 280, 304, 354, 368, 392, 402, 464, 496, 498, 516, 550, 552, 642, 644, 680, 708, 748, 770, 774, 784, 786, 834, 836, 840, 860, 978, 1026, 1032, 1040, 1044, 1056, 1062, 1064, 1068, 1074, 1092, 1104, 1120, 1184, 1232, 1266, 1312, 1362, 1376, 1410, 1504
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OFFSET

1,1


COMMENTS

Positions of zeros in A324648. Fixed points of A318458, also positions of the records in the latter.
Intersection with A324652 gives A324643.
The odd terms are: 7425, 76545, 92565, ... (A324897).


LINKS

Antti Karttunen, Table of n, a(n) for n = 1..20000
Index entries for sequences related to binary expansion of n
Index entries for sequences related to sigma(n)


MATHEMATICA

Select[Range@ 1600, BitAnd[#, DivisorSigma[1, #]  #] == # &] (* Michael De Vlieger, Apr 21 2019, after Vincenzo Librandi at A318458 *)


PROG

(PARI) for(n=1, oo, if(bitand(n, sigma(n)n)==n, print1(n, ", ")));


CROSSREFS

Cf. A318458, A324648, A324652.
Cf. A000396, A324643, A324897, A324898 (subsequences).
Sequence in context: A044970 A316291 A090502 * A324643 A119425 A006039
Adjacent sequences: A324646 A324647 A324648 * A324650 A324651 A324652


KEYWORD

nonn


AUTHOR

Antti Karttunen, Mar 14 2019


STATUS

approved



