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Search: id:A020668
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A020668 Numbers of form x^2 + 4 y^2. +0
1
0, 1, 4, 5, 8, 9, 13, 16, 17, 20, 25, 29, 32, 36, 37, 40, 41, 45, 49, 52, 53, 61, 64, 65, 68, 72, 73, 80, 81, 85, 89, 97, 100, 101, 104, 109, 113, 116, 117, 121, 125, 128, 136, 137, 144, 145, 148, 149, 153, 157, 160, 164, 169, 173, 180, 181, 185, 193, 196, 197, 200, 205, 208 (list; graph; listen)
OFFSET

1,3

COMMENT

Numbers that can be expressed as both the sum of two squares and the difference of two squares; the intersection of sequences A001481 and A042965. - T. D. Noe (noe(AT)sspectra.com), Feb 05 2003

CROSSREFS

Cf. A001481, A042965.

Sequence in context: A042948 A126001 A073320 this_sequence A020934 A094004 A067271

Adjacent sequences: A020665 A020666 A020667 this_sequence A020669 A020670 A020671

KEYWORD

easy,nonn

AUTHOR

David W. Wilson (davidwwilson(AT)comcast.net)

page 1

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Last modified July 25 07:41 EDT 2008. Contains 142293 sequences.


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