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A357651
Sliding numbers which are products of two distinct primes.
0
65, 133, 205, 254, 502, 785, 2005, 10001, 15689, 16265, 20005, 31282, 79405, 100001, 156314, 390881, 1000001, 3906506, 10000001, 100000001, 244144721, 5000000002, 6103532009, 152587956161, 762939584197, 3814699887065, 19073486852413, 38146972918394, 200000000000005, 10000000000000000001
OFFSET
1,1
COMMENTS
A squarefree subsequence of numbers of the form p + q where 1/p + 1/q = (p + q)/10^k for some k >= 1.
EXAMPLE
65 = 5*13 (65 = 25 + 40 and 1/25 + 1/40 = 0.065).
133 = 7*19 (133 = 8 + 125 and 1/8 + 1/125 = 0.133).
15689 = 29*541 (15689 = 64 + 15625 and 1/64 + 1/15625 = 0.015689).
244144721 = 641*3808814096 (244144721 = 4096 + 244140625 and 1/4096 + 1/244140625 = 0.000244144721).
CROSSREFS
Intersection of A103182 and A006881.
Sequence in context: A352982 A355543 A348759 * A294169 A073631 A285300
KEYWORD
nonn,base
AUTHOR
Massimo Kofler, Oct 07 2022
EXTENSIONS
More terms from Hugo Pfoertner, Oct 08 2022
STATUS
approved