A139535 Smallest prime starting with 1 that contains exactly n 0's.

101, 1009, 10007, 100003, 1000003, 100000037, 100000007, 1000000007, 100000000019, 100000000003, 10000000000037, 100000000000031, 1000000000000037, 10000000000000061, 100000000000000013

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..100

Mathematica

sp0[n_]:=Module[{c=1, d}, While[d=FromDigits[Join[PadRight[{1}, n+1, 0], IntegerDigits[ c]]]; DigitCount[d, 10, 0]>n||CompositeQ[d], c=c+2]; FromDigits[ Join[ PadRight[ {1}, n+1, 0], IntegerDigits[c]]]]; Array[sp0, 20] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 30 2020 *)

Crossrefs

Cf. A037053, A003617, A139536.

Sequence in context: A164842 A082276 A069597 * A139536 A115820 A115773

Adjacent sequences: A139532 A139533 A139534 * A139536 A139537 A139538

Keyword

nonn,base

Author

Lekraj Beedassy, Apr 25 2008

Status

approved