A098598 -id:A098598 - cp's OEIS frontend

A097208 a(n) is the least k such that A098598(k) = n.

40, 24, 19, 17, 16, 10, 23, 21, 92, 313, 155, 551, 2575, 757, 13537, 5525, 35133, 33953, 332975, 355573, 3157535, 1571573, 2732737, 3775555, 5737571, 37332775

Offset: 0

Jason Earls, Sep 17 2004

a(27) = 75787577. No more terms < 10^8. - David Wasserman, Dec 27 2007

			a(3)=17 because it is the least number that contains 3 primes in the sequence 1,7,8,15,23,38,61,99,160,259.

Cf. A098598.

f[n_] := Block[{id = IntegerDigits[n], t = Floor[ Log[10, n] + 1], b}, Do[ b[i] = id[[i]], {i, t}]; b[i_] := b[i] = Plus @@ Table[b[i - j], {j, t}]; k = t + 1; While[b[k] < n^2, k++ ]; Count[ PrimeQ[ Table[b[i], {i, k - 1}]], True]]; t = Table[0, {50}]; Do[c = f[n]; If[ t[[c + 1]] == 0, t[[c + 1]] = n; Print[c, " = ", n]], {n, 10, 12000000}]; t (* Robert G. Wilson v, Oct 07 2004 *)

Corrected and extended by Robert G. Wilson v, Oct 07 2004

a(25), a(27) and better definition from David Wasserman, Dec 27 2007

A097373 Numbers n such that there are no primes in a sequence formed from the t digits of n where the latter terms are given by rule b(i)=sum of t previous terms and the primes are counted from initial t digits up to the largest term < n^2; where zeros are located in A098598.

Original entry on oeis.org

40, 44, 46, 48, 60, 64, 66, 68, 69, 80, 84, 86, 88, 90, 96, 99, 194, 400, 404, 406, 408, 440, 444, 446, 448, 460, 464, 466, 468, 480, 484, 486, 488, 600, 604, 606, 608, 609, 640, 644, 646, 648, 660, 664, 666, 668, 669, 680, 684, 686, 688, 690, 696, 699, 800

Offset: 1

Jason Earls, Sep 18 2004

			194 is in the sequence because 1, 9, 4, 14, 27, 45, 86, 158, 289, 533, 980, 1802, 3315, 6097, 11214, 20626 contains no primes.

Cf. A098598.

A097376 Numbers n such that there is exactly one prime in a sequence formed from the t digits of n where the latter terms are given by rule b(i)=sum of t previous terms and the primes are counted from initial t digits up to the largest term < n^2; where ones are located in A098598.

Original entry on oeis.org

24, 26, 28, 36, 39, 42, 62, 63, 82, 93, 116, 148, 149, 168, 189, 204, 206, 208, 240, 244, 246, 248, 260, 264, 266, 268, 280, 284, 286, 288, 306, 309, 360, 366, 369, 384, 390, 396, 399, 402, 411, 414, 419, 420, 424, 426, 428, 441, 442, 462, 465, 482, 491, 498

Offset: 1

Jason Earls, Sep 18 2004

			148 is in the sequence because
1,4,8,13,25,46,84,155,285,524,964,1773,3261,5998,11032,20291 contains one prime.

Cf. A098598.

cp's OEIS Frontend

A097208 a(n) is the least k such that A098598(k) = n.

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A097373 Numbers n such that there are no primes in a sequence formed from the t digits of n where the latter terms are given by rule b(i)=sum of t previous terms and the primes are counted from initial t digits up to the largest term < n^2; where zeros are located in A098598.

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A097376 Numbers n such that there is exactly one prime in a sequence formed from the t digits of n where the latter terms are given by rule b(i)=sum of t previous terms and the primes are counted from initial t digits up to the largest term < n^2; where ones are located in A098598.

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