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.

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A101434 Composite numbers which are the product of non-twin primes.

Original entry on oeis.org

4, 8, 16, 32, 46, 64, 74, 92, 94, 106, 128, 134, 148, 158, 166, 178, 184, 188, 194, 212, 226, 254, 256, 262, 268, 296, 314, 316, 326, 332, 334, 346, 356, 368, 376, 388, 422, 424, 446, 452, 466, 502, 508, 512, 514, 524, 526, 529, 536, 554, 586, 592, 614, 628, 632
Offset: 1

Views

Author

Walter Carlini, Jan 18 2005

Keywords

Examples

			74 = 2*37, 529 = 23*23.
		

Crossrefs

Cf. A100819.

Programs

  • Mathematica
    nn = 150; p = Prime[Range[nn]]; t = {2}; Do[If[p[[n + 1]] - p[[n]] != 2 && p[[n]] - p[[n - 1]] != 2, AppendTo[t, p[[n]]]], {n, 2, nn - 1}]; Select[Range[2, t[[-1]]], ! PrimeQ[#] && Complement[Transpose[FactorInteger[#]][[1]], t] == {} &] (* T. D. Noe, May 21 2013 *)

Extensions

Corrected and extended by Arkadiusz Wesolowski, May 21 2013
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