cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A066722 Numbers that can be expressed as the sum of two primes in exactly six ways.

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%I A066722 #21 Apr 22 2025 14:07:20
%S A066722 60,66,72,100,106,110,116,118,134,146,166,172,182,212,248,332
%N A066722 Numbers that can be expressed as the sum of two primes in exactly six ways.
%C A066722 No other terms below 10000. I conjecture there are no further terms in this sequence and A067188, A067189, etc.
%C A066722 _R. K. Guy_ (Jan 14 2002) remarks: "I believe that these conjectures follow from a more general one by Hardy and Littlewood (probably in Some problems of 'partitio numerorum' III, on the expression of a number as a sum of primes, Acta Math. 44(1922) 1-70)."
%H A066722 <a href="/index/Go#Goldbach">Index entries for sequences related to Goldbach conjecture</a>
%t A066722 y = Select[Flatten@Table[Prime[i] + Prime[ j], {i, 500}, {j, 1, i}], # < Prime[500] &]; Select[Union[y], Count[y, #] == 6 &] (* _Robert Price_, Apr 22 2025 *)
%Y A066722 Numbers that can be expressed as the sum of two primes in k ways for k=0..10: A014092 (k=0), A067187 (k=1), A067188 (k=2), A067189 (k=3), A067190 (k=4), A067191 (k=5), this sequence (k=6), A352229 (k=7), A352230 (k=8), A352231 (k=9), A352233 (k=10).
%K A066722 nonn
%O A066722 1,1
%A A066722 Peter Bertok (peter(AT)bertok.com), Jan 13 2002