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A098970 Numbers k such that (12*k)^2 can be expressed as the sum of the cubes of two distinct primes. 5
19, 67695, 411292, 1134035, 1184876, 2112836, 2455255, 4073384, 11293009, 16171470, 18589912, 34388501, 63609329, 63711615, 117446600, 166530856, 284034387, 449805631, 637548135, 685361103, 783484793, 888180400, 1121365940 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This sequence resulted from a discussion on the seqfan mailing list started by Ed Pegg Jr.

Dean Hickerson and Paul C. Leopardi have shown that if a and b are distinct primes with a^3 + b^3 = c^2, then c must be divisible by 12.

The numbers 12*k form a subsequence of A099426. - Hans Havermann, Oct 24 2004

All terms of this sequence are of the form M*N*(3*M^4+N^4)/2 for some pair M,N of relatively prime positive integers of opposite parity. For each n, A099806(n)^3 + A099807(n)^3 = (12*A098970(n))^2. - James R. Buddenhagen, Oct 26 2004

LINKS

Table of n, a(n) for n=1..23.

James Buddenhagen, Two Primes Cubed which Sum to a Square.

CROSSREFS

Cf. A099426.

Cf. A099806, A099807, A099808, A099809.

Sequence in context: A145851 A182374 A034207 * A172751 A013764 A078353

Adjacent sequences:  A098967 A098968 A098969 * A098971 A098972 A098973

KEYWORD

nonn

AUTHOR

Hugo Pfoertner, Oct 24 2004

EXTENSIONS

More terms from James R. Buddenhagen, Oct 26 2004

STATUS

approved

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Last modified June 16 14:16 EDT 2021. Contains 345057 sequences. (Running on oeis4.)