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A325241 Numbers > 1 whose maximum prime exponent is one greater than their minimum. 6
12, 18, 20, 28, 44, 45, 50, 52, 60, 63, 68, 72, 75, 76, 84, 90, 92, 98, 99, 108, 116, 117, 124, 126, 132, 140, 147, 148, 150, 153, 156, 164, 171, 172, 175, 180, 188, 198, 200, 204, 207, 212, 220, 228, 234, 236, 242, 244, 245, 252, 260, 261, 268, 275, 276, 279 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k), so these are Heinz numbers of integer partitions whose maximum multiplicity is one greater than their minimum (counted by A325279).

LINKS

Table of n, a(n) for n=1..56.

FORMULA

A051903(a(n)) - A051904(a(n)) = 1.

EXAMPLE

The sequence of terms together with their prime indices begins:

  12: {1,1,2}

  18: {1,2,2}

  20: {1,1,3}

  28: {1,1,4}

  44: {1,1,5}

  45: {2,2,3}

  50: {1,3,3}

  52: {1,1,6}

  60: {1,1,2,3}

  63: {2,2,4}

  68: {1,1,7}

  72: {1,1,1,2,2}

  75: {2,3,3}

  76: {1,1,8}

  84: {1,1,2,4}

  90: {1,2,2,3}

  92: {1,1,9}

  98: {1,4,4}

  99: {2,2,5}

MATHEMATICA

Select[Range[100], Max@@FactorInteger[#][[All, 2]]-Min@@FactorInteger[#][[All, 2]]==1&]

CROSSREFS

Positions of 1's in A062977.

Cf. A001221, A001222, A001694, A051903, A051904, A052485, A056239, A112798, A118914, A325240, A325259, A325270, A325279.

Sequence in context: A072588 A267117 A187039 * A072357 A054753 A098899

Adjacent sequences:  A325238 A325239 A325240 * A325242 A325243 A325244

KEYWORD

nonn

AUTHOR

Gus Wiseman, Apr 15 2019

STATUS

approved

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Last modified August 23 12:02 EDT 2019. Contains 326222 sequences. (Running on oeis4.)