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.

A085497 Primes p having no partition into distinct divisors of p+1.

Original entry on oeis.org

2, 13, 37, 43, 61, 67, 73, 97, 101, 109, 113, 137, 151, 157, 163, 173, 181, 193, 211, 229, 241, 257, 277, 281, 283, 313, 317, 331, 337, 353, 373, 397, 401, 409, 421, 433, 443, 457, 487, 491, 523, 541, 547, 563, 577, 601, 613, 617, 631, 641, 653, 661, 673, 677
Offset: 1

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Author

Reinhard Zumkeller, Jul 03 2003

Keywords

Examples

			p=13, divisors of p+1=13+1=14 that are not greater 13: {1,2,7} with sums of distinct summands 1,2,3=2+1,7,8=7+1,9=7+2 and 10=7+2+1, therefore 13 is a term.
		

Crossrefs

Subsequence of A085492.

Programs

  • Mathematica
    seqQ[p_] := Module[{d = Most[Divisors[p+1]]}, SeriesCoefficient[Series[Product[1 + x^d[[i]], {i, Length[d]}], {x, 0, p}], p] == 0]; Select[Range[700], PrimeQ[#] && seqQ[#] &] (* Amiram Eldar, Jan 13 2020 *)

Formula

A085496(a(n)) = 0.

Extensions

More terms from Amiram Eldar, Jan 13 2020