A231629 First of 7 consecutive deficient numbers in arithmetic progression.

801339, 962649, 7353339, 21964299, 41642139, 48049689, 55455939, 89034939, 89851449, 92253849, 105259539, 107948379, 109455339, 114295449, 116754939, 122349369, 135575979, 156009849, 159521049, 173645439, 188586699, 192674169, 193137849, 220301769, 221355125

Offset

1,1

Links

Shyam Sunder Gupta, Table of n, a(n) for n = 1..126

Example

801339, 801341, 801343, 801345, 801347, 801349, 801351 is the smallest set of 7 consecutive deficient numbers in arithmetic progression so 801339 is in the list.

Mathematica

DefQ[n_] := DivisorSigma[1, n] < 2 n; m = 2; z1 = 2; cd = 1; a = {}; Do[If[DefQ[n], If[n - z1 == cd, m = m + 1; If[m > 6, AppendTo[a, n - 6*cd]], m = 2; cd = n - z1]; z1 = n], {n, 3, 1000000000}]; a

Crossrefs

Cf. A005100, A231623, A228964, A231624, A231625, A231626, A231628.

Sequence in context: A106781 A112451 A235006 * A231090 A237298 A069338

Adjacent sequences: A231626 A231627 A231628 * A231630 A231631 A231632

Keyword

nonn

Author

Shyam Sunder Gupta, Nov 11 2013

Status

approved