A179232 Numbers in A075728 which are not one less than some prime.

120, 186, 264, 450, 504, 552, 696, 978, 1208, 1440, 1444, 1848, 2034, 2744, 4320, 4410, 5376, 6888, 7020, 9264, 9968, 10944, 10989, 13952, 16080, 19152, 23160, 29280, 31410, 34464, 38928, 39648, 49544, 56880, 60480, 67266, 73200, 78480, 82800, 91440, 102312

Offset

1,1

Comments

The first 30 terms of A075728 are equal to prime(k)-1 for some k. The first term here, n = 120, satisfies |sigma(n) - 2*n| = n. - Michel Marcus, Nov 02 2013

Links

Donovan Johnson, Table of n, a(n) for n = 1..1000

Formula

A075728 \ A006093.

Prog

(PARI) lista(nn) = {rec = -1; for (n=1, nn, d = abs(sigma(n) - 2*n); if (d > rec, if (! isprime(d+1), print1(d, ", ")); rec = d; ); ); } \\ Michel Marcus, Nov 02 2013

Crossrefs

Cf. A006093, A075728.

Sequence in context: A337479 A322377 A247851 * A056994 A288461 A114823

Adjacent sequences: A179229 A179230 A179231 * A179233 A179234 A179235

Keyword

nonn

Author

Artur Jasinski, Jul 04 2010

Extensions

More terms from R. J. Mathar, Jul 05 2010

A-number typo corrected by R. J. Mathar, Jul 16 2010

Status

approved