A324771 - OEIS

A324771

Numbers divisible by at least one of their prime indices > 1.

6, 12, 15, 18, 24, 28, 30, 36, 42, 45, 48, 54, 55, 56, 60, 66, 72, 75, 78, 84, 90, 96, 102, 105, 108, 110, 112, 114, 119, 120, 126, 132, 135, 138, 140, 144, 150, 152, 156, 162, 165, 168, 174, 180, 186, 192, 195, 196, 198, 204, 207, 210, 216, 220, 222, 224, 225

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OFFSET

1,1

COMMENTS

A prime index of n is a number m such that prime(m) divides n.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

The sequence of terms together with their prime indices begins:

6: {1,2}

12: {1,1,2}

15: {2,3}

18: {1,2,2}

24: {1,1,1,2}

28: {1,1,4}

30: {1,2,3}

36: {1,1,2,2}

42: {1,2,4}

45: {2,2,3}

48: {1,1,1,1,2}

54: {1,2,2,2}

55: {3,5}

56: {1,1,1,4}

60: {1,1,2,3}

66: {1,2,5}

72: {1,1,1,2,2}

75: {2,3,3}

78: {1,2,6}

84: {1,1,2,4}

MATHEMATICA

Select[Range[100], Or@@Cases[If[#==1, {}, FactorInteger[#]], {p_?(#>2&), _}:>Divisible[#, PrimePi[p]]]&]

CROSSREFS

Complement of A324849.

Cf. A003963, A056239, A112798, A120383, A289509, A290822, A304360.

Cf. A324695, A324846, A324847, A324848, A324850, A324851, A324852, A324853.

Sequence in context: A315615 A315616 A091011 * A104210 A356736 A066312

Adjacent sequences: A324768 A324769 A324770 * A324772 A324773 A324774

KEYWORD

nonn

AUTHOR

Gus Wiseman, Mar 18 2019

STATUS

approved